The present study examines sex differences in early language acquisition in Catalan by analysing lexicon and morpho-syntax. A total of 883 parents of children aged 16–30 months completed the MacArthur-Bates CDI. Children were grouped by sex and age (16–20, 21–25, 26–30 months). Results from 2×3 ANOVAs showed that girls outperformed boys in vocabulary, MLU, and Complexity Index. However, post hoc analyses indicated significant differences only in the 21–25-month group. Significant age-by-sex interactions in morpho-syntax suggest varying developmental patterns. These findings indicate that girls’ early advantage appears only at intermediate ages.
Aguilar‐Mediavilla et al. (Wed,) studied this question.