Preschoolers Infer Listeners from Age-Related Variation in Maternal Child-Directed Speech

Child-directed speech (CDS) varies systematically with the recipient child’s age. The present study examined whether children aged 3–6 years are sensitive to this within-register variation and use it to identify the intended recipient. Turkish-speaking children living in Türkiye (N = 76) listened to recordings of mothers addressing each of their two children, one younger and one older, and were asked to identify which child a given recording was directed at. The stimuli were drawn from six mother-sibling pairs whose children ranged in age from 6 to 68 months and differed from each other by 29 to 59 months. Accuracy improved significantly with participant age, with performance exceeding chance at approximately 3.6 years. Neither the age gap between recipient children, the recipients’ absolute ages, nor participants’ sibling status predicted performance. These findings demonstrate that sensitivity to age-related variation in CDS emerges during the preschool years, extending prior work beyond broad adult- versus child-directed register distinctions to within-register variation.