Evaluating early coparenting using the Lausanne Trilogue Play observational procedure: Guidance for infant-family practitioners from an International Coparenting Collaborative

Abstract

Since the early 1990s, coparenting - a conceptual framework connecting clinical insights from structural family therapy to theory and research on development of infants and toddlers within relationship systems - has brought new perspective to family and developmental science while hinting at ramifications for clinical practice. Coparenting theory and research evolved side-by-side with careful, intensive study of mother-father-child triangular relationships in families with very young children, work that expanded in recent years to include studies of other coparent-child triangular systems, such as those involving mothers, grandmothers, and infants. Until now, however, there has been no coordinated expert guidance for bringing concepts expounded in research studies of coparenting and triangular relationships to practitioners who work in infant-family mental health and family therapy contexts. In 2022, a Collaborative of family-oriented infant mental health experts from seven countries, all bringing proficiency in assessing and working with coparenting and triangular family dynamics in research or clinical settings, organized to review and identify common agreed-upon behavioral manifestations of coparenting during triangular interactions. Recognizing four central dimensions capturing how coparents and children organize when interacting together as a triangular system (engagement, teamwork, conflict, and child focus), the International Coparenting Collaborative (ICC) explains in this report how a standardized observational assessment, the Lausanne Trilogue Play (or LTP) can be used to identify coparenting strengths and challenges and elevate practitioners’ attunement to coparenting dynamics within their therapeutic contexts.

Since the early 1990s, coparenting - a conceptual framework connecting clinical insights from the field of structural family therapy (S. Minuchin, 1974) to theory and research on the formative experiences of infants and toddlers within the relationship systems supporting their early development (P. Minuchin, 1985; McHale & Lindahl, 2011) - has brought a new perspective to family and developmental science (Feinberg, 2003; Jones et al., 2007; Maccoby, Depner & Mnookin, 1990; McHale, 1995, 1997; McHale et al., 2002a, b; Teubert & Pinquart, 2010). Coparenting theory and research have evolved side-by-side with careful and intensive study of mother-father-child triangular relationships in families with very young children (Fivaz-Depeursinge & Corboz-Warnery, 1999; Gordon & Feldman, 2008; Hedenbro, 2006). Especially generative in this work has been the Lausanne Trilogue Play (LTP), a semi-standardized family observation procedure that has gained enhanced visibility and use in the infant-family mental health field (see McHale et al., 2018 for a detailed historical review).

In this article, our aim is to raise practitioners’ awareness of coparenting within their therapeutic contexts, illustrating how LTP observations can be used to evaluate coparenting strengths and challenges in a manner that can also facilitate communication with parents about these coparenting dynamics. Observations are indispensable when working with families of pre-verbal infants and young children, for observed patterns of interaction illuminate families’ propensities for engagement by coparents and children, for coparental teamwork and conflict, and for the family’s degree of child focus. Taken together, these four central constructs offer clinicians a meaningful read on how family members navigate family interactions, and the readily discernible behavioral indicators offer therapists grounded opportunities to explore coparenting dynamics with parents themselves during later conversations that can include video-feedback. Our focus in this article will hence be specifically on infant-family observations. Self-report measures of coparenting also do exist (for a review, see McHale, 2011), though evidence for their utility in clinical settings is scant, and hence self-reporting is not a focus of this report.

Observations of Families with Infants and Toddlers: Relevant Historical Considerations

Observations of families are certainly not new – the study of “normal family processes” had an initial heyday in the late 20^th century. However, historically, many of the best-known family observation instruments (i.e., Beavers & Hampson, 1990; Miller et al., 2000; Olson & Killorin, 1985) of that time were not conceived with families of infants and toddlers in mind (Favez et al., 2010). Some assessments did, and do highlight communication and affective behavior of parents, toward one another or toward the child. However, none are truly systemic, because the infant’s own non-verbal behavior is not typically considered. This is because measures are principally language-based, and hence usually overlook contributions of preverbal infants. Existing systems were also not designed to highlight or reflect sequential processes of behavior – which are so useful in exploring family dynamics with coparents - relying instead on molar units echoing clinical constructs.

The longstanding inattention to infant contributions and influence in therapeutic contexts has recently been highlighted as a perplexing, widespread failing of contemporary family practice (Opie et al., 2023 a; 2023b). However, because infant contributions are a core element of the LTP observational procedure, the LTP offers a uniquely useful option for clinicians who work with families of infants and toddlers. Over the past 20 years, LTP observations have proven useful in explorations with both community and clinical samples (e.g. Fivaz-Depeursinge et al., 2006; Mensi et al., 2020), including families experiencing post-partum breakdown (Philipp et al., 2009); families of children on the autism spectrum (Mazzoni et al., 2017; Oppenheim et al., 2023), and post-divorce families (Lavadera et al., 2011). However, while the LTP is acceptable to families who present with clinical problems (e.g., Fivaz-Depeursinge et al., 2004, 2007, 2009; Philipp et al., 2009), there has heretofore been no coordinated expert guidance explaining how practitioners might bring concepts and approaches validated in observational studies of coparenting and triangular relationships to everyday infant-family mental health and related practice settings. Some basics about the LTP follow.

The LTP Procedure as Used with Families of Infants and Young Children.

The LTP consists of four different “Parts”, each of which reflects one of four interactive configurations possible in three-person triangular systems (Corboz-Warnery et al., 1993). In Part 1, one parent actively plays with the baby while the second coparent is simply present. Next comes a second “2+1”, or Part 2, in which the two coparents switch roles. Part 3 is a “three-together”, inviting both coparents and child to play as a threesome with one another. Finally, in Part 4, there is a third and final “2+1” wherein the coparents actively engage with one another as the child is assigned the third-party position. The LTP is introduced to the family with a set of standardized instructions.

Sequences of behavior enacted during the LTP offer glimpses into family structure and process. LTP experts often videorecord LTP sessions and select short excerpts from recordings (reflecting engagement patterns amongst the three family members, instances of coparenting teamwork and conflict, and/or examples illustrating the coparents’ sensitive reading of the child, or child focus). These clips can be shared with parents in later video feedback sessions, during which both resources and challenges shown during the sequences of family interaction are highlighted and explored. Readers interested in the use of videofeedback are referred to Fivaz-Depeursinge and Corboz-Warnery (1999) and Fivaz-Depeursinge and Philipp (2014).

Behavioral indicators identified during seminal LTP studies.

Our focus in this report will be on the observed behaviors that can serve as indicators of engagement, teamwork, conflict and child focus during LTP interactions, and on how these coparenting observations can inform work in therapeutic contexts. However, some background and context may be useful first. Behavioral indicators have been the principal focus of LTP assessments since the time of the seminal LTP investigations (Fivaz-Depeursinge & Corboz-Warnery, 1999) filmed at the Centre d’Etude de la Famille (CEF) studio in Lausanne, Switzerland. At the CEF, a microanalytic coding system was developd to assess nonverbal behaviors – in particular, gazes, body postures, and affect expressions. Trained, expert coders watched LTP video recordings with this elaborate system, called Grille d’Evaluation des Interactions Triadiques du Centre d’Etude de la Famille, or GETCEF – “Grid for Evaluating Families of the Center for Family Studies” (Fivaz-Depeursinge et al., 1998).

The GETCEF scrutinized (a) the three family members’ mutual body orientations, (b) the distances between their pelves, torsos and heads, and (c) the direction of their eye gaze. CEF researchers found that family members signal their mutual availability and readiness to interact (which they called a “participation” function) through body position and orientation – and principally via the positioning of their hips. To maintain their role in the interaction (an “organization’ function), the orientations and position of their torsos were especially telling. Establishing participation and organization allowed family members to share a common focus, signified by how they oriented their heads and their gazes (which the CEF researchers labeled ‘focalization’). Finally, successful fulfillment of all three of the prior functions increased the likelihood that positive and negative emotions would be shared. This last function was documented through a Gestalt reading of facial-vocal-gestural expressions and of displays of emotional interest (or ‘affect sharing’, e.g., Fearnley Shapiro et al, 1997). These four functions are hierarchically interlinked in the sense that adequate fulfillment of each is necessary to fully realize the next (Fivaz-Depeursinge, 1991; Frascarolo et al., 2004).

Unfortunately, the sheer level of skill needed to use GETCEF made it impractical for use by family clinicians. Favez and colleagues (2011) did try to transform the GETCEF coding process into a system accessible to a wider audience, creating a Family Alliance Assessment Scales (FAAS) to evaluate the structural features of participation, organization, focalization and affect sharing. But the FAAS, too, proved too advanced for individuals not conversant with the CEF system of evaluation, and its creators concluded that it too was impractical for use by individuals who had not been intensively trained.

Closing the Research-Practice Disconnect: The International Coparenting Collaborative

Recognizing this research-practice disconnect, a Collaborative of family-oriented infant mental health professionals from seven countries, each bringing substantial expertise in assessing and working with coparenting and triangular interactions, formed in 2022 to review and identify common behavioral manifestations of coparenting observable during LTP interactions. The intent of this International Coparenting Collaborative (ICC; McHale et al., 2023) was not to create yet another LTP classification system. Instead, its objective was to highlight the LTP’s utility as a procedure that most family clinicians could call upon in their everyday practice settings to assist them in formulating hypotheses when observing coparent-infant interactions. Rather than proposing a tallying of discrete behaviors toward assignment of a total score or classification, the ICC aim is to promote recognition of four main dimensions (i.e., Engagement, Teamwork, Conflict, and Child Focus) central to how coparents organize when joining together with their child as a triangular system, and to promote understanding of why and how such systematic observations of coparenting behavior in the LTP can be of significant value in work with families of infants and young children. Clinicians who have interest in using the LTP for classification purposes are encouraged to refer to the expansive LTP research literature.

Before presenting this guidance, the sections below offer a brief history of relevant past empirical research in which the ICC’s efforts are embedded. We highlight work establishing the relevance of observed coparenting and family dynamics during infancy, major indicators that have been studied in capturing observed coparenting dynamics, and the importance of the child’s own contributions. Having laid this foundation, we then examine how specific behavioral indicators observable during LTP interactions can be called upon to inform clinical work that might seek to influence coparenting in the family system.

Evidence for the Relevance of Observed Coparenting and Family Dynamics during Infancy: A Brief Review

Clinicians working from family systems perspectives have for several decades recognized the unique value and weight of relationship processes within the full family unit. There has been a longstanding focus on family triangles (Bowen, 1978; Donley, 1993; Friedman, 2014), most commonly mother-father-child triangles. This triangle has also been central in psychoanalytic thought, for understanding processes of separation-individuation (Henderson, 1982), splitting in the service of ambivalence (Juni, 1995), and navigation of the oedipal crisis (Brickman, 1993; Frank, 1988). However, the idea that the infant’s intrapsychic process during the first year of life includes being part of a triad was never central in psychodynamic theory (Abelin, 1975; Lemche & Stoeckler, 2002) - in large part because only in recent decades were the advanced social competencies of infants below the age of one fully verified and acclaimed (Fivaz-Depeursinge et al., 2005; McHale et al., 2008; Tremblay & Rovira, 2007).

The significance of evaluating coparenting by attending to triangular dynamics during infancy progressively gained credence and credibility following several prospective, longitudinal studies documenting the coherence of relationship adjustment across developmental time, and the formative impact of coparenting and triangular processes during the infant and toddler years on young children’s social and emotional adjustment. We review this literature first, highlighting conceptual and methodological similarities and distinctions germane to the current report.

Lab Based Studies of Coparenting during Triadic Interactions

As the LTP procedure was being developed in Lausanne, Philip and Carolyn Cowan in Berkeley, California were involved in a study of the transition to new parenthood (Cowan & Cowan, 1992). They, along with other research groups investigating parenthood transitions (for review, see Kuersten-Hogan & McHale, 2021), recognized the birth of a first child as a stage in the family life cycle requiring changes in family structure, roles, and routines that caused stress for married couples as they adjusted to the changes (Mattessich & Hill 1987; Goldberg 1988). The Cowans devised a preventive intervention, offered prenatally, to try to ease the transition for new parents and exert protective effects for marital relationships. Their analyses focused on many domains of family life (Cowan & Cowan, 2005), though like others in the field at that time they were particularly concerned with quality of functioning within relationship dyads – husband-wife, mother-child, father-child. Their landmark study substantiated ripple effects in families of prenatal group interventions, some of which were short-lived, others of which persisted across developmental time (Cowan & Cowan, 1992). The Cowans’ study stopped short of examining triadic relationship systems, however, priming a new look at coparenting in mother-father-infant triangles during the child’s second half year of life.

Coparenting and Triadic Interactions during Infancy: A Coparenting and Family Rating Approach.

McHale (1988; 1995) - capitalizing on a rising topic of the times in the infancy field, action in social context and adult scaffolding of early infant experience (Kaye, 1982) - brought mothers and fathers together as coparents to jointly engage 8–11-month-old infants in object-mediated exploration and play. With parents and babies positioned in a triangular configuration, he provided play materials babies could explore and use for more advanced coordinated actions (banging, stacking, inserting). The adults could follow infants’ leads in exploring the affordances of objects (shape, texture, sound potential) and/or intervene to show infants varying ways objects could be interrelated to one another in juxtaposition. Only vague directives were given regarding what to play with, for how long, or with whom – families took whatever approach they saw fit. The triadic play sessions were recorded and later reviewed with an eye toward approach strategies, affective tone, and behavioral dynamics among the three family members at play.

Several strategies were observed, some child-centered (following babies’ interests and initiatives), some adult-centered (parents dictating and guiding the flow of activity), and some mixed (parents sometimes guiding, sometimes accommodating infant interests and/or the two parents showing noticeably different propensities in guiding, following – or acceding). Certain parents supported, augmented, or embellished the initiatives between the coparent and child. Others contested the actions of the coparent, interfering with their activities, proposing different ones, and even sometimes mumbling sarcastic or critical jabs at the other parent. A few absented themselves from the triadic engagement altogether, sitting back and allowing the other parent to dominate the play activity. Families also differed in engaging together with a businesslike, methodical air or with warmer, animated and/or cheerful affective dispositions.

Trained coders evaluated each parent’s overall warmth and engagement with the baby and their warmth with one another, their cooperativeness as coparents, their competitive actions and verbal sparring, and the extent to which sessions were adult- (or child-) centered. Discrepancy scores were calculated to represent differences in the warmth and engagement of the two parents with the baby (higher scores signifying that one parent was warmer and/or more engaged than the other), and a total family warmth score reflected the extent to which warmth was observed in the interactions among the three family dyads. These seven scores (cooperation, competition, verbal sparring, warmth discrepancies, engagement discrepancies, total family warmth, and adult vs. child-centeredness) yielded three higher-order factors, reported by McHale (1995) – hostility-competitiveness (low to high competition, verbal sparring, and adult-centeredness), family harmony (low to high cooperation and total family warmth) and parenting discrepancy (low to high differences in parental engagement and warmth exhibited toward baby). This Coparenting and Family Rating System (CFRS; McHale et al., 2000a) was used in an independent Canadian lab with slightly older children. The factor structure identified in McHale’s (1995) analyses replicated exactly (McConnell & Kerig, 1999), suggesting that the observable coparenting processes identifiable from infant/child-coparent play – i.e., conflictual, harmonious, and differentially engaged – were telling.

Studies of Coparenting, Triadic and Family Interactions with Toddlers and Preschoolers: Expanded Evaluation Approaches.

The CFRS was employed in subsequent studies of a preschool-aged sample in Berkeley (McHale et al., 1999) and a toddler-aged sample in Worcester, Massachusetts (McHale et al., 2000b). For both samples, McHale and his colleagues introduced a broader range of age-relevant activities for families that focused both on teaching and unrestricted play. For the toddler sample, they used both contained teaching activities and games (electronic boards, a tower-building game) and less constrained activities (a pretend family meal, a game of horseshoes, free exploration of a toybox containing gender-neutral and gender-stereotypical toys) because different types of activities (teaching, physical action) showcased different talents and comfort levels of the two coparents. Their pretend family meal was later expanded to a formalized structured assessment, the PicNic game (Frascarolo-Moutinot & Favez, 2005), for use with both younger and older children, and families with multiple children. A coding system for PNG interactions: the Revised-PicNic Assessment Scales (Favez et al., 2016), focused on some of the same components as the CFRS such as the interparental relationship (distinguishing coparenting from conjugal relationship) and the overall tone of the family interaction (family warmth).

The most ambitious study of this era was the “Families through Time” (FTT) longitudinal study of the transition to coparenthood (McHale, 2007), which followed families from pregnancy through the child’s first few years of life. FTT researchers captured the essence of coparenting at each of multiple time points (prenatally, 3-, 12-, 30-, and 54-months post-partum) using multi-method approaches. Readers are referred to McHale (2007) for comprehensive details of the various assessment strategies at different ages. Of particular interest to the current article was the FTT adaptation of the LTP for coparenting assessments at 3 months post-partum. Though it had been studied at the CEF in Lausanne for nearly two decades, the LTP had only begun to earn wider visibility after a unique initiative (Fivaz et al., 1994) that evolved into a collaborative of scholars from Switzerland (Lausanne and Basel), Sweden, France, England and the U.S. The collaborative undertook multiple independent efforts at evaluating triads, ranging from a macro assessment of the “quality of whole family trilogue” (von Klitzing et al., 1999) to micro-coding of behavioral sequences in families (Hedenbro & Lidén, 2001, 2002). The LTP analyses newly undertaken in the FTT study, by contrast, were themselves firmly rooted in the earlier coparenting observational investigations using the lens of the CFRS.

During 3-month home visits in the FTT study, videorecords of triangular interactions were assessed using the CFRS and a companion tool capturing micro-events on a time-sampling grid (Lieberson et al., 2004; see Table 1). First, microanalytic events relevant to the constructs of interest (e.g., a third-party parent flirting with the baby during the 2+1, the coparents mis-coordinating during the 3-together by advancing competing activities in different modalities), were coded with focus on both the active and third-party parent in the 2+1; interactive behaviors of the coparents in the 3 together; and verbal remarks throughout. In a second stage, coders used the CFRS to generate global, clinical ratings of family process. The global ratings considered behavior noted during the time sampling, but also transcended mere counts to provide overall estimates of the family’s coparenting processes and their esprit de corps. As reported by McHale and Alberts (2003), several key sequences of interaction observed by the micro-raters appeared influential in informing higher-order determinations about core family dynamics and processes. For example, the greater the number of interruptions of partner-baby interaction, both by mothers and by fathers, the more likely clinicians were to rate the coparents as competitive. As McHale and Jenkins (2023) have noted, this observational study provided empirical corroboration for the time-honored family therapy practice of identifying and punctuating meaningful interaction sequences in the ebb-and-flow of family assessment and therapy sessions (Minuchin, 1974).

Table 1:

Overview of CFRS Time-Sampling Codes (from Lieberson et al., 2004)

1. Codes used to rate Active Coparent

• Vocalizes Parent talks or makes sounds to the baby.

• Touches Parent makes physical contact with the baby.

• Expresses Positive Affect Parent shows clear display of affection or positive emotion (such as smiling, laughing, musical quality to voice tone).

2. Codes used to rate Third Party Coparent

• Resonates Responds (e.g., changes posture or facial expression) to the interaction between the partner and baby.

• Disengages Physically absents themselves, closes off body posture, or looks away for three or more seconds.

• Interferes/Flirts Interferes (smiles, vocalizes, makes faces at the baby) but does not disrupt the interaction taking place between the Active Coparent and baby.

• Interferes/Distracts Interferes with interaction to a greater extent than simply flirting (e.g., stroking or tugging at baby’s outfit).

3. Codes used to rate the triadic interaction:

• Shared Positive Affect Simultaneous display of positive emotions by both coparents.

• Active Co-Action Coparents work or act in accord while simultaneously engaged with the baby (e.g., team together to encourage baby to babble.)

• Benign Cooperation Coparents respectfully take turns and give space to one another but don’t team together in same activity such as presenting the same game or activity.

• Disengages Parent orients away from interaction between coparent and baby by looking away for three or more seconds or closing off body posture.

• Miscoordination Coparents send separate, conflicting messages to the infant, but quickly recognize they are doing so and adjust so that only one message is offered.

• Active Competition Coparents give sustained dual or separate and conflicting messages to the infant.

• Shared Parental Moments Communication exchanged directly between coparents, signified by facial, physical and/or (most often) verbal expression of warmth that is expressed between the adults and not triangulated through the baby.

• Remarks

Remarks and gestures are coded for individual parents throughout the three Parts of the LTP.

Cooperative remarks indicate support of the other (e.g., “She likes that.”)

Neutral remarks signify comments with no positive or negative valence (e.g., “She sees herself in the mirror”; “He’s getting sleepy”.

Disagreeing remarks signify lack of consensus about an event. However, there is no indication that the divergent remarks are hostile or contentious (e.g., responding to a coparent who thinks the baby can see themself in the mirror, the other may reply “I’m not sure she does”).

Competitive remarks signify comparisons between the coparents. (e.g., “That’s right, look at Mommy, not Daddy", "How come mommy gets a smile and I don’t?"

Help-Seeking remarks include requests for assistance or clarification.

Further Strategies for Identifying Meaningful Behavioral Sequences in Families.

The CFRS was the first and most widely used observational system validated for families with infants, but it was not the only one. For example, in the collaborative LTP project noted earlier, analyses of videotaped LTP sessions from the Swedish sample employed a Child and Parents Interactive Coding System (CPICS; Hedenbro & Lidén, 2002). Ratings were generated on a micro-level, sequence by sequence, and the CPICS focused on the contributions of both the coparenting adults and of the child to the triadic interactions. As did Lieberson et al.’s (2004) micro-analytic approach used in the FTT study (Table 1), the CPICS took stock of the coparent’s behavior while in the Third-Party Position - supporting, disturbing and/or interrupting the ongoing interaction (Hedenbro & Lidén, 2002). Not explicitly conceived as a study of coparenting per se, coding categories nevertheless included numerous behaviors and action sequences (i.e., turn-taking, tempo, inclusion vs. exclusion, initiative/contribution, non-verbal/verbal affirmation, synchronization) that signified engagement, mutual respect, and collaboration – all important micro-indicators of good coparenting teamwork.

We have already discussed the FAAS (Family Alliance Assessment Scales) which, in addition to assessing structural features of participation, organization, focalization and affect sharing also included ratings for dynamic features of the interactions (communication mistakes and repair of these mistakes); for coparenting support and conflicts; and for infant involvement and regulation. Inclusion (engagement) of each partner, defined by the orientation of body postures and gazes, helped define Participation. Focalization included parental scaffolding, or stimulation adapted to the child’s age and state (capturing the extent of the coparents’ child focus). Affect sharing included family warmth as an indicator. Hence, though attending to different levels of detail, the FAAS captured similar elements of coparenting as did CFRS scales applied to the LTP interactions. The fact that the FAAS was too advanced for individuals not already conversant with the CEF system of evaluation was not especially surprising - ease of uptake is a common issue in family science. For example, van Ijzendoorn et al. (2005) noted that intervention efforts with narrower aims are easier for the average intervener to learn than ‘broadband’ interventions requiring intensive training of highly qualified interveners. This adage also appears true for coparenting observations and assessments.

To bridge this research-practice gap, in each major section that follows, we outline in some detail how commonly observed behavioral manifestations in the LTP map onto the four major coparenting dimensions (Engagement, Teamwork, Conflict, and Child Focus). Although these indicators may apply to all types of family configurations, we will focus on interactions involving mothers, fathers and infants, as this is the family configuration most widely studied in the 4-Part LTP. We will draw specific attention to ways in which the nature of family members’ engagement can be expected to vary and manifest in each of the four Parts. In providing this expert guidance, we will also present brief case examples to help bring each to life.

Assessing Coparenting during the LTP: Understanding Engagement

Coparents’ mutual engagement has proven time and again to hold psychological significance for the child and family, with significant levels of disengagement or exclusion indicative of a more challenged family system (Corboz et al, 1993, Elliston et al., 2008; Fivaz-Depeursinge & Corboz-Warnery, 1999; McHale, 1995). As detailed above, in three-person units, the LTP provides insights into the participatory dispositions of both coparents and child as it proceeds through its four Parts. Standardized instructions are provided (Supplement 1), and “appropriate” activity is understood somewhat differently depending upon the specifically assigned roles for each Part as given in the instructions. However, in every Part, the behavior of all 3 parties is crucial to attend to. The main question of interest regarding the first of the four main coparenting dimensions identified by the ICC – observed Engagement – is whether all family members show appropriate interest, engagement, and participation during the family interaction. As documented in CEF studies, key indicators of engagement include each person’s body posture and orientation and each person’s gaze orientation (the observer making note of whether each person’s gaze stays inside, or wanders away from, the triangle). Voluminous empirical LTP research has demonstrated that these signs are the most meaningful indicators for observers to pay attention to when determining how engaged family members are in the play.

So, what exactly should a clinician be on the lookout for, especially in Parts 1, 2 and 4, when one of the 3 people has been explicitly assigned a role of third-party (i.e., asked to be simply present)? Despite being in the third-party position, that person’s behavior nonetheless conveys meaning and is important to watch as the two active parties interact together. Looking first at Parts 1 and 2, there are three potential engagement stances a third-party coparent (TPC) can take when assigned to that role. For simplicities sake, these can be characterized as:

• Not watching

• Watching silently but not reacting

• Watching and reacting

When observing the TPC in Parts 1 and 2, the practitioner must note (as signals of level of engagement) both posture and gaze - gaze alone is not sufficient:

Not watching:

As signs of non-participation (withdrawal, exclusion): the TPC may be observed episodically gazing away, sometimes looking at a clock, cell phone or window. In so doing they may be observed reclining or sitting askance with a body posture not oriented toward the active dyad. In some cases, a TPC may be observed “zoning out”, seeming psychologically absent (manifesting a blank/dull facial expression). In some cases, a TPC may simply sit still and limp. Such a posture, if sustained, would typically be a sign of non-engagement, but the practitioner should consider if the TPC might still be Watching but Not Reacting.

Watching but Not Reacting connotes a passive form of engagement. In contrast to a TPC who is not watching, a TPC who is watching but not reacting does appear to be interested, supportive, and sometimes even studying the interaction of the AC and child. Posturally, the TPC signals attentiveness and interest to the AC-child interaction by orienting hips and torso toward the AC and baby, and may lean forward, maintain an enlivened body posture, and show small movements - but does so without grinning or mirroring affect.

Watching and reacting is the most positive form of TPC engagement. Posturally, the TPC is always oriented toward AC and child, with the most obvious sign of engagement seen in the TPC’s facial reactions as s/he reacts to what’s happening in the active dyad. A reaction on the TPC’s face to moments of delight between AC and child is typically a clear sign of such positive connection. Facial expressions of delight are typically not manifested, of course during moments when nothing much is happening between AC and child. Even so, some parents do occasionally derive pleasure from even seemingly mundane exchanges between AC and baby.

Finally, the baby’s posture and gaze are likewise always meaningful. Coparents who are collaborating positively and staying in role maximize the likelihood that the infant will maintain engagement with the AP. Infants sometimes still do bid to the TPC, as if wishing to share their attention and affect with the TPC too. However, sustained engagement with the AP in Parts 1 and 2 is one signifier of the child’s propensity for flexibly engaging with both adults and can be seen as an indirect indicator that the coparental alliance encourages mutual engagement.

Case example 1 (a Part 1): Mother is playing a game moving her face closer to the baby’s while intoning “who’s my baby boy? - then back as the baby giggles. Father sits erect in his chair, shoulders hunched slightly forward, smiling broadly each time the baby giggles, but keeping his distance and not interfering. He is clearly connected - watching and reacting.

Case example 2 (a different family’s Part 1): Mother smiles and bobs her head from side to side, twice leaning to the left to recapture the baby’s attention when (as he does on two occasions), her son turns his head slightly away. Father sits slumped back in his chair, watching dispassionately with no facial changes. The second time mother follows baby’s turn away, he looks off in a different direction. While the father is watching and not reacting for much of the interaction, he can also clearly be seen not watching for part of the episode.

These guidelines above are all of course general in nature. As with the second case, it is seldom the case that any given family member maintains a single posture (not engaged/watching not reacting/watching and reacting) continuously through the duration of Part 1 or 2. Further, infants themselves developmentally can be expected to gaze at objects around the middle of the second year, sometimes as though wishing to share their interest in objects with parents. Hence it is the overall sense of the 3-person connection that constitutes the most important takeaway when gauging engagement from Parts 1 and 2.

In Part 3, since the invitation is explicitly for all three family members to play together, a coparent or child not optimally engaged signals this through gaze breaks, distorted body posture, and muted or pained affective displays. The age of the child is an important consideration; in an LTP completed with a very young baby (under 4–5 months), failure to gaze at a parent is a strong sign of exclusion. Very young infants will typically seek direct communication, motivated to communicate through dialogue and regulation. For any age infant, systematically turning away from the parents is considered non-participation. However, for toddlers and older preschoolers, it is not uncommon for the child to episodically co-orient to attractive toys or objects in the room, as if to share their attention with them – then return gaze to the family. Given these normative ebbs and flows that can vary as a function of developmental stage, the practitioner’s attention in Part 3 is usually best focused on the overall extent to which the threesome shows sustained and/or recurring bouts of shared attention and affect.

Also in Part 3, infants typically make numerous “triangular bids”, gazing back and forth between the coparents as if to share their pleasure, surprise or distress with both. The infant’s capacity for three-way interactions was initially documented by Tremblay (2007) in a study of shared attention and again shown by Bradley (2017), examining groupness in infants. Triangular bids are the clearest signs of the infant’s capacity to share her attention and affects with more than one partner at a time (Fivaz-Depeursinge et al, 2005; McHale et al, 2008).

Within Part 4, the child’s participation can be challenging to evaluate at certain ages. Many infants and toddlers do show interest in watching the parents, frequently even signaling a wish to be included in their interaction as the adults turn to orient to one another. Even older children (especially those who remain in their seat and do not wander the room) can sometimes be seen responding to parent emotions. Other children, however, leave their seat and wander the room to play as adults engage together. Hence child behavior in the third-party role in Part 4 is not as reliable an indicator of participation as is coparent behavior within the third-party role in Parts 1 and 2. However, it can still be noted and in some cases may be of clinical interest. A more telling clinical indicator in Part 4, however, is the coparents’ propensity to draw and maintain a healthy boundary between subsystems (and to engage together themselves).

If the practitioner sees recurring signs in the LTP that one or more family members is not optimally engaged, they would take note. For example, observing that a coparent repeatedly checks a cell phone when in the TPC role, or watches blankly without taking opportunities to connect behaviorally or affectively in Part 3 would lead to a hypothesis about disengagement that could be verified/further tested out through other observations. With the infant, triangular bids (shifting gaze orientation from one parent to the other, then back again) is a prime sign of the infant’s engagement in the family triangle and should always be attended to. In every case, the aim in recording these observations is to later determine if corroborating evidence of non-participation or exclusion exists, and if so, the reasons why all members do not seem to have the same equitable opportunity for interest, engagement, and access (Fivaz-Depeursinge et al. 2009).

Assessing Coparenting during the LTP: Understanding Teamwork

Teamwork is the essence of generative coparenting. Empirical analyses verify that cooperation, collaboration, and warmth expressed between coparents represent far more than simply the absence of conflict (McHale, 1995; McConnell & Kerig, 1999) and, as a separate and distinct family process and dynamic, are strongly predictive of young children’s socioemotional adjustment (Mangelsdorf et al., 2011; McHale & Rasmussen, 1998). In assessing Teamwork, the principal question of interest is whether there is sustained, convincing evidence that each coparenting adult respects the other as part of the team. From the perspective of observation, also of interest is whether parallel (and sometimes differing) parental objectives, commonplace in most families, can be coordinated during the play. At any age, it is most ideal for children if the adults manage to work contentedly together as a team during the LTP assessment.

In Parts 1 and 2, Parent-parent teamwork can be harder to see, but an actively engaged (watching-reacting), non-interfering parent may prompt a hypothesis that underlying teamwork and solidarity exists. This hypothesis can be verified or disconfirmed by coparental behavior in Part 3. Also, though the thrust of this article is about coparenting, we note here that during Parts 1 and 2 the teaming of the child and parent is still worth the observer noting. Specifically, if the clinician identifies any moments when a baby responds particularly positively to a parent style or tempo (e.g., to gentle soothing, to more lively animation) this footage can help the clinician piece together concrete feedback about strengths within the family to be reviewed with the coparents later to emphasize their Child Focus.

LTP research has always attended closely to the transitions between Parts of the assessment, as these are a key moment for observing coordination and teamwork between coparents. When the Active Coparent (AC) initiates the transition away from themselves and to the next Part, this can sometimes be viewed as a potential indicator of teamwork. Then, once Part 3 is underway, it is typically easier to observe the extent to which coparents are inclined to show teamwork.

For many families, Part 3 is a challenge, as each coparent takes to individually engaging the child based on their own personal preferences and interests. In such families, the coparents “do their own thing” and pay little attention to contributions of the other coparent. This presentation signifies an absence of teamwork. Positive signs of teamwork are most clearly in evidence when coparents coordinate together in joint and shared activity with the child.

Case example: After mom has completed her 2+1, dad takes a turn, then notices the mother sitting patiently and leaning forward with seeming anticipation. He says, “why don’t you play with us too, mommy?”. He draws back momentarily as the mother leans in and the baby orients to her – a well-coordinated transition from Part 2 to Part 3. The mother smiles and resumes making “popping” noises with her mouth that she’d made during Part 1. Father picks up the game and begins to emulate mother, causing the baby to look his way first quizzically, and then breaking into a smile. Later, mother and baby initiate a game of peek-a-boo, and father assists baby by covering his eyes. As the baby began to fuss, mother takes him out of the seat, and father pats his son on the back. The coparents show multiple signs of reading one another’s initiatives, joining the coparent without contradicting them, and conveying warm, sunny affect both with one another and with the baby, all hallmarks of strong teamwork.

Shared and well-coordinated activity (such as the coparents in the example did in sharing the same activity chosen by the other – peekaboo, mouth noises) is a high-level indicator of cooperation. Optimal functioning can be seen in moments when there is synchronization among all three participants, amidst the ebb and flow of the interaction – threesome intersubjective communion (Burgin & von Klitzing, 1995; Fivaz-Depeursinge et al., 2012; Stern, 2008). In synchronous moments the baby may also display joy, and delight in the experience of all 3 family members being truly together. Such truly triangular sharing is noteworthy, significant, and always worth emphasizing in video feedback with families (e.g., Philipp et al., 2023).

More common is respectful turn taking between adults, implicit coordination that can itself be a sign of good teamwork. A common presentation is for one coparent to recline their torso and “take a break” for a spell while still actively watching and supporting the other. The air of ongoing support may be expressed facially (through smiles), verbally (by commenting) or both. Play between the other coparent and child continues seamlessly without the break-taking coparent abruptly leaning back in to co-stimulate the child. In all cases the observing practitioner should center their observations of Part 3 not just on whether the parents are teaming well but on whether they are co-attuned to and adjusting to the child and her signals.

Finally in Part 4, Teamwork can also be assessed. Cooperation can sometimes be intuited from observing the coparents’ efforts to support one another as they try to engage in discussion with the child present. One salient indicator is whether a dialogue between them, rather than a monologue dominated by just one adult, emerges. In other instances – if one parent does display greater leadership for keeping the conversation going – Teamwork can still be intuited if the less active coparent remains attentive to the more active coparent and is not sidetracked by monitoring the baby continuously.

Assessing coparenting during the LTP: Understanding Conflict

In the 1990s, developmental psychologists began closely attending to child-related conflict, elevating such conflicts as central signifiers of coparenting distress (Grych et al., 1993; Kerig, 1996). Conflict perturbs even very young infants (Crockenberg et al., 2007; Graham et al., 2013; Moore, 2010), and within the context of LTP interactions, a key question is whether the coparents manage to limit and contain competitive, antagonistic exchanges. In general, sustained verbal conflict in LTP interactions is unusual. However, behavioral conflict is much more commonplace; at least minor, temporary misattunement is almost inevitable and conflict repair is an important facet of communication. Infant-family mental health interventions can work to help parents recognize and contain conflict, and to become more skilled at repair when conflict does occur (Gold & Tronick, 2020). In making use of LTP observations, the practitioner stays on the lookout for signs suggesting competitiveness, disregard for the other, antagonistic behavior or comments, and (more mildly, but also important) TPC interruptions.

In Parts 1 and 2, the most relevant signs of conflict are usually interference by the TPC who, uninvited, comes out of role to interfere, criticize, or “help” the AC. The intrusiveness and interference by a TPC can sometimes be driven by an impulse to be supportive (which on a continuum is sometimes less concerning), but in every case it is important to observe how the AC responds to the interference. Even if interference is intended to be supportive, the AC may react to the intrusion negatively or even hostilely. Conversely, “helping” interference could also be graciously accepted by the AC and perceived as being supportive. Hence much depends on the reaction of the AC. Still, the practitioner will want to take note, particularly if the TPC’s “help” did not seem necessary, as this observation can sometimes help generate useful hypotheses about the nature of the coparenting dynamic.

Sometimes, interference by the TPC signifies a desire not to feel left out or excluded. Such intrusions can be considered an “in-between” index creating a hypothesis about (but not in and of itself confirming) a dynamic of conflict/competition. Confirmatory information from other behavioral samples and parent reports would be needed. If, however interference is more clearly critical in nature, this is usually problematic, especially if the child is observed to react/ respond to the disturbance. In short, any signs of TPC interference create hypotheses for the practitioner that s/he will want to further explore – intrusions are not themselves diagnostic, but rather hypothesis-generating. Indeed, whenever any of the critical indicators summarized in these guidelines is noted, the practitioner must aim to locate each observation within a larger overall narrative or set of common coparenting themes and threads for this particular family.

In Part 3, conflict and competition are easier to see. Sometimes open competition with critical comments between parents occurs (e.g., a parent, in sarcastic tones, speaking for the baby, “I don’t like this game”). Such nattering is almost always significant. More typically, competitive exchanges are mild and subtle. In fact, it is commonplace to see one or more brief moments of miscoordination, defined as the two parents engaging in different (dissonant) forms of stimulation at the same time. When this occurs, the practitioner can watch to see if the miscoordination resolves quickly and naturally. If fleeting, only episodic, and followed by repair – i.e., one coparent recognizing the miscoordination, leaning back, and allowing the other coparent to continue their game or interaction – there is minimal concern. If it continues and becomes a theme in the interaction, miscoordination is more worrisome, as it has the potential to dysregulate the child. Sometimes, the degree of coparenting conflict can even lead the parents to “lose sight” of the child – the adults get so caught up in their coparenting difficulties/ miscoordinations that the child appears to come first no longer. In such cases, the sustained and observed competition can become one target for later reflection and intervention.

Case example: In a family led by two late adolescent parents, both mother and father were lively and good-humored, while also vying for their baby’s attention and engaged in one-upmanship in an apparent competition to make their baby laugh. The father also unilaterally took the lead on calling for transitions between Parts. In a rather unusual display, at one moment during Part 3 the mother switched positions with the father, exasperated that the baby continued to look in father’s direction following the transition from Part 2 to 3. She also began replicating tactics that had been successful for the father during Part 2 to make the baby laugh. At one point during Part 3 she moved the father’s hands out of the way, exclaiming, “It’s my turn!” The father, in reaction jokingly retaliated by blocking the mother’s kisses to the baby – all the while, with the baby watching intently, and at one point drawing his body back seeming perplexed by the flurry of activity around but not involving him. Though unusually competitive, the coparents also showed indicators of warmth and passion.

Certainly, conflict in the above interaction was indisputable. The aim of the LTP is sharing together and experiencing warmth and pleasure, and so throughout each Part of the LTP, the practitioner must be attuned for tension in the climate created by and between coparenting adults. When there are consistent negative comments, verbal sparring, conflict, and antagonism between coparents, positive interactions and shared pleasure are usually subdued. But in some cultural and subcultural groups, including many lower income families who endure multiple life challenges from outside the family, purposeful dry humor, joking sarcasm and irony during coparenting exchanges are often displayed. In the case example described, which was competitive and mistuned to the infant, the parlays between coparents were carried out in a spirited, almost playful manner, with a minimum of callous hostility. Of principal interest would have been the problems in attunement to the child’s signals and sensibilities, belied at one point when he drew his body back in response to the activity level. Determining whether competitive exchanges such as those above are happy-go-lucky and harmless, or a sign of deeper disquiet can be complicated. At minimum such observed interactions would prompt hypotheses about underlying conflict and hostility. But such hypotheses, which practitioners must always own as their own curiosity about what they observed, need to be checked out with the family.

Last, regarding transitions between Parts of the assessment, any time a TPC initiates the transition away from the AC and to themselves, this might be construed as a potential sign of conflict/interference. Though there is no infallible determining factor, one relevant index that should be considered is the length of time the AC had been playing with the baby. If the AC had had only brief and insufficient time with the child to play, the TPC’s intrusion may be a sign of competition/interference. If on the other hand there had been considerable, ample time for the AC to play with the infant or young child in the 2+1, the TPC’s transition bid or “intrusion” may not hold the same significance.

Assessing Coparenting during the LTP: Establishing the Extent of a Child Focus

Effective coparenting requires that all coparenting adults be accurately attuned to the child’s needs and sensibilities. Ideally, coparents in triadic interactions should be responsive to children’s signals, paralleling what one could expect from one parent during dyadic interactions with the child (Ainsworth, 1978). Because the referral question when a young child is brought to a clinic is often related to emotional or behavioral concerns, an important assessment aim involves evaluating coparenting as it centers on that particular child and her needs. Perhaps the most significant – but also, most easy to overlook – clue to capturing quality of coparenting will be the observed sequalae of contributions and signals the child him or herself displays during the interaction (Fivaz-Depeursinge et al., 2005; Hedenbro & Rydelius, 2014).

The practitioner must hence be deliberate in attending to the child and her signals during the LTP, and noting how the coparents respond to those, as the main question of interest regarding observed Child Focus is the extent to which both coparenting adults recognize and affirm the child’s bids, signals and – more generally – contributions. Infants contribute to interactions long before they are old enough to show intentionality – through grimaces, head turns, squirms, slumping posture, and the like. Especially significant for coparenting assessments is each adult’s predilection to recognize and affirm child behavior and emotion. In Parts 1, 2 and 3, the practitioner should note whether the coparents read and respond to the child’s signals, even if these signals are weak. Infants and very young children invariably experience moments of stress during the LTP, and the practitioner can sometimes even detect selective infant reactions to coparental conflict, ranging from avoidance (turning away) to attention seeking. More subtle signs from a baby not being given sufficient voice can include sighs, coughing, frowns, and even drooling or regurgitating. Babies, even very young ones, often send such signals in the context of an overstimulating interaction, and their signals can easily go unnoticed if clinicians are not attentive to them. It is doubly important to note such signs if the child’s parents are not attending to them; usually, if signs of discomfort are attended to sufficiently and early, discomfort is less likely to escalate into full blown child distress.

Whether or not the child shows discomfort, it is also important to establish whether the coparents provide openings for the baby to “guide” the flow of the interaction. Many adults unilaterally dictate what happens during every moment of the interaction, entertaining, teaching, and directing the child; in the language of the CPICS, “the turns of the parties do not interlace but rather appear as one-way dialogues” (Hedenbro & Liden, 2002). The practitioner can take note of quality of parental scaffolding, of overall child centeredness (from following the child’s interests throughout; to sometimes following child interests, sometimes not; to everything being 100% adult-driven), and of the intensity of coparents’ stimulation of the baby (over vs. under).

Sensitivity is a key component in threesome play. Tempo of play can overstimulate the child, but insensitivity can also come in the form of under-stimulation. Pertinent signs include not attending to the child’s signs of needing support, engagement, or help. An older preschool-aged child may signal discontent by physically getting up from their seat, leaving the interaction and doing other things. But with a baby or younger child, the practitioner must watch the child to determine if they are drawn to engage – or not – with the active parent(s). In cases where adults are noted to be overbearing, a point for reflection and a potential therapeutic aim might be in helping the coparents afford the baby a bit more room and opportunity for voice.

Case example: The LTP literature abounds with detailed case examples illustrating how coparents can work together – or not – to scaffold infants’ interest, attention and affect regulation during triangular interactions. For example, Fivaz-Depeursinge and colleagues (2012) provide an unusually detailed account of an LTP characterized by multiple “serious interactive errors”. Part 3 began with the father asking “What game are we going to play? Let’s show our hands!” and mother joining him in placing their open palms in front of the 9-month-old’s face. The baby instantly became agitated, looking at first father, then mother with eyes scrunched, and hit his seat with his hand. When mother leaned forward, the baby raised his arms to be picked up, and she empathically responded “Later”. Father offered his index finger, but the baby pushed it away, averting his gaze. The mother opened her hands, proposing a “high five” and father obliged. Mother made the baby high five father’s hand, expressing pleasure. But when they took the baby’s hands in theirs, he fussed – before suddenly switching to cooperate, putting his hand into the mother’s. Father mistook the child’s gesture as a greeting, and the baby broke down again, flapping his arms and fussing.

In the illustration above, the family was unable to separate from the unsuccessful games the coparents organized. Despite the baby’s repeated protests, the parents continued to align together trying to engage him in their game. Though their “united coparental front” might have suggested good teamwork, the Part 3 games were rigidly controlled by the father, with mother simply submitting and aligning with him, however unwillingly. As a result, the family’s misattuned child focus persisted, largely insensitive to the child’s signaling of needs.

In summary, the baby can teach the clinician a great deal about the quality of interaction in their family. Though clinicians frequently make note of whether one parent is more adept than the other at reading the child’s signals, the objective of a coparenting assessment is to develop a fuller picture of how the two adults position themselves as coparents with and for the child.

Implications and Applications

For several decades, the LTP has been used as an evocative paradigm for eliciting family interactions in studies of coparenting and family process, and in therapeutic encounters with a wide range of families including those struggling with mental health issues, divorce, and child autism. However, this work has seldom found its way into everyday clinical practice, where infants and toddlers have seldom been fully integrated into systemic case formulations and interventions. This article represents an important step in building such a bridge, providing a synthesis of central dimensions and indicators drawn from the extant evidentiary base on observed coparenting in families of infants and young children, and offering concrete, useable guidance translatable to everyday clinical practice.

Such a synthesis is long in coming; as has recently been highlighted in the family therapy literature (Opie et al., 2023 a.; b), pre-verbal infants and toddlers are regularly overlooked and rarely integrated meaningfully as full participants in family and systemic interventions. The work featured in this report provides guidance practitioners can use within their therapeutic contexts to elevate mindfulness about coparenting in families of infants and young children. By attending to LTP sequences, patterns and trends in engagement by family members, coparental teamwork and conflict, and child focus, therapists can formulate generative hypotheses about the family’s coparenting dynamic, explore them collaboratively with parents during case conceptualization, and potentially target specific pattern interruptions or changes in treatment planning.

The ICC has provided more comprehensive guidance about systemic formulations in other publications (McHale et al., 2024). Herein, our focus has been principally on enhancing the recognition of relevant behavioral indicators exemplifying both family resources and family challenges. By noting and recording relevant infant-coparent interactions, practitioners are then in position to meaningfully consider and reflect upon them in subsequent work with the family. Organizing notes of key sequences encapsulating engagement, conflict, teamwork, and child focus in everyday practice certainly does not require use of a formal coparenting rating scale; one such sample recording grid for practitioner use is presented in Supplement 2. For research purposes, those interested in validated rating scales that have been used with the LTP might consider the FAAS or CFRS. The literature reviewed at the beginning of this article can provide the deeper guidance needed for high quality research investigations.

Larger scale, coordinated, longitudinal studies of clinical populations in which the LTP and its constructs and indicators are systematically studied - though exacting and time-consuming - are needed to help further advance this important arm of inquiry. Though the validity of the coparenting observations and constructs and the behavioral indicators indicative of those constructs have been well-established empirically, few larger scale investigations have validated those same constructs and indicators with clinical samples. This is of course in some ways a specious concern, for the coparenting field itself has its roots in structural family theory and therapy (Minuchin, 1974). Moreover, the CEF LTP studies, trial interventions and smaller N inquiries have all engaged families presenting with clinical problems, from the very beginning. However, while collectively the ICC LTP experts who articulated the key indicators detailed in this article brought expansive experience in working with families from myriad cultural, ethnic and socioeconomic backgrounds, larger scale LTP investigations focused on clinical populations can offer further insights and provide additional construct validation. .

In such work, attention must also be given to family structures and systems beyond the mother-father-child triangular system studied most extensively. This work has begun (Coates & McHale, 2018; D’Amore et al., 2022; 2024; Lavadera et al., 2011; Liang et al., 2021; Mazzoni et al., 2016; McHale et al., 2013; Salman-Engin et al., 2018), but the LTP’s pertinence for clinically referred families from understudied groups requires additional attention before these preliminary guidelines can be applied with the same confidence to diverse family compositions, genders, and ethnic and cultural backgrounds. For now, based on decades of empirical and clinical investigation, we see merit in considering the LTP as one means of structuring assessments and evaluating coparenting strengths and challenges in families with infants and very young children. We hope the direction provided in this article is of value to family therapists and other clinicians seeking to better integrate infants in their efforts with families.

Public Significance Statement.

This article details how observational studies of mother-father-infant triads in a standardized assessment procedure have uncovered patterns of interaction illuminating how families coparent. It explains how to distinguish readily observable indicators of coparenting engagement, teamwork, conflict, and child focus enacted during such triangular interactions, so that these patterns can be explored with and understood by families.