Table 1.

Intraclass correlations for the relationships between twin parental depression and offspring internalizing/externalizing problems (95% confidence intervalsin parentheses)

	MZ twin families			DZ twin families
	Twin 1	Twin 2	Offspring 1	Twin 1	Twin 2	Offspring 1
Parental depression and offspring internalizing
Twin 2	0.35 (0.26–0.43)			0.14 (0.04–0.23)
Offspring 1	0.26 (0.21–0.30)	0.07 (0.00–0.14)		0.26 (0.21–0.30)	0.04 (−0.03–0.10)
Offspring 2	0.07 (0.00–0.14)	0.26 (0.21–0.30)	0.16 (0.06–0.25)	0.04 (−00.03–0.10)	0.26 (0.21–0.30)	0.10 (0.01–0.19)
Parental depression and offspring externalizing
Twin 2	0.35 (0.26–0.43)			0.13 (0.04–0.22)
Offspring 1	0.18 (0.14–0.23)	0.09 (0.02–0.16)		0.18 (0.14–0.23)	0.04 (−0.03–0.10)
Offspring 2	0.09 (0.02–0.16)	0.18 (0.14–0.23)	0.22 (0.11–0.31)	0.04 (−0.03–0.10)	0.18 (0.14–0.23)	0.14 (0.05–0.22)

Twin 1 is the parent of child 1. Twin 2 is the parent of child 2. Correlations are taken from constrained saturated models in which variances and means were constrained across twin order and zygosity and parent–child covariances were constrained across zygosity.