Abstract

Aisha, age 24 months, sees her older sister trip over a toy and squeals “Kiki fell!” At 30 months her doll falls behind the couch, and she asks “Where dolly falled?” At 48 months her computer mouse falls behind a stack of computer manuals under the desk, and she asks “Where did that silly mouse fall?” Both her world and her sentences are getting more complex as she gets older, but there is one oddity: the past‐tense verb fell shows a U‐shaped developmental pattern. Aisha gets it right at 24 months, wrong at 30 months, and right again at 48 months. Why?