A progressive consonant-substitution pattern in a typically developing child

The purpose of this paper was to describe and explain an unusual consonant substitution (default) pattern in the early lexical repertoire of a typically developing boy. Ben was audiotape recorded monthly from age 2;2-2;8 (years; months), to follow an unusual substitution pattern, initially observed between 1;6 and 1;7 diary notations. Data from each recording period were analysed with reference to (a) consonant repertoire, and (b) default and non-default features present. Data are presented for three periods of [l] substitution: initially, for a glide /w/ (age 1;6-1;7), next, as a substitution for word-initial fricatives /s/, /z/ and (age 2;2-2;3), and finally, in place of /r/ in consonant +/r/ clusters, in place of /j/ in initial position, and as a between-word liaison age 2;72;8. It is shown that preferences for specific features, consonant vowel interactions, and syllable positions may be implicated in motivating this [l] substitution at specific points over time. The observed pattern is explained with reference to universal and child-specific factors and adds further evidence for variability that exists among typically developing children.