Table 2.

Early-, middle-, and late-developing sounds in English and Spanish.

Language	Early	Middle	Late
English a (Shriberg, 1993)	/m, b, j, n, w, d, p, h/	/t, ŋ, k, ɡ, f, v, ʧ, ʤ/	/ʃ, ð, s, z, Ɵ, l, ɹ/
Spanish b (Fabiano-Smith & Goldstein, 2010a)	/ɲ, t, m, n, k, x/	/s, f, p, ʧ, β, ɣ/	/l, ð, r, ɾ/

^a The sound /ʒ/ was excluded from analysis by Shriberg (1993).

^b The spirants /β, ɣ, ð/ were analyzed in place of the voiceless stops because they are more likely to be the phoneme, rather than the allophone, in the stop–spirant alternation (Barlow, 2003b).