Overall, infants learned the legal labels but not the illegal labels, for evidence with younger infants; for alternative findings. However, there were also differences in learning associated with vocabulary size. Infants with larger vocabularies showed stronger phonotactic constraints on label learning; they showed greater differentiation of legal versus illegal labels than infants with smaller vocabularies. In related work, found that preschool-aged children learned high phonotactic probability more readily than low-probability words. Children with larger vocabularies showed stronger phonotactic effects than children with smaller vocabularies; they had a greater advantage for high-probability labels than for low-probability labels. Taken together, these findings suggest that with vocabulary development, young learners may develop more stringent criteria for the sound sequences that are possible word forms, thereby constraining the search for words to link with meanings. This selectivity may promote efficient lexical acquisition in two ways. First, infants will avoid wasting cognitive resources entertaining illegal word forms as labels for concepts. Second, successful learning of new legal or canonical words may strengthen emerging representations of the phonotactic constraints and probabilistic patterns present in the ambient language.