Regularization in the face of variable input: Children's acquisition of stem-final fricative plurals in American English

From a young age, children go through a stage of leveling irregular forms. They are also known to probability-match variable phenomena. However, it is still unclear how children treat phenomena that are both irregular and variable. Does their tendency to overregularize take over, leading them to seize on the regular occurrences and produce them at an even higher rate than adults, or do children probability-match in these cases? In order to study this question, we turn to the variably voiced plurals of English nouns that end in a voiceless fricative, like leaves, houses, and paths. We find that children seem to probability-match for /s/-final and /θ/-final stems (e.g. houses, paths), but not for /f/-final stems (e.g. leaves). This finding has implications for our understanding of first language acquisition, and how learners acquire words with multiple processing requirements.