We investigated the influence of exposure to phonologically similar words on four-year-olds’ acquisition of novel object words. In Experiment 1, hearing phonological neighbours before learning a new word did not influence children’s novel word productions. In Experiment 2, when children heard the phonological neighbours of a novel word after learning a new word, they correctly produced the target word more often than children who did not receive this exposure. These findings suggest that exposing children to similar sounding words after a novel word was introduced may have helped maintain a representation of that word in working memory, leading to enhanced word learning.