Purpose: Family size is linked tightly with children's language development. Yet, we have a limited understanding of the associations between family size, specifically the number of adults and siblings, and children's social communication skills, particularly in children from diverse linguistic environments. The present study examined the effects…

Purpose: The current study addresses a gap in the literature regarding syntactic development of adolescent boys with fragile X syndrome (FXS) and Down syndrome (DS). Specifically, we ask whether syntactic skills plateau or continue to change during adolescence for these groups and whether the profile of syntactic change differs between boys with…