The present study examined whether length of bilingual experience and language ability contributed to cross-situational word learning (XSWL) in Spanish-English bilingual school-aged children. We contrasted performance in a high variability condition, where children were exposed to multiple speakers and exemplars simultaneously, to performance in a condition where children were exposed to no variability in either speakers or exemplars. Results revealed graded effects of bilingualism and language ability on XSWL under conditions of increased variability. Specifically, bilingualism bolstered learning when variability was present in the input but not when variability was absent in the input. Similarly, robust language abilities supported learning in the high variability condition. In contrast, children with weaker language skills learned more word-object associations in the no variability condition than in the high variability condition. Together, the results suggest that variation in the learner and variation in the input interact and modulate mechanisms of lexical learning in children.
