People use different communication patterns based on the context and who they are addressing. These differences, known as linguistic register, are common across human speech and recognized early in development. Here, we examine 4-11-year-old American children's (N = 227) ability to use linguistic registers to determine a speaker's addressee as…

Research on sources of individual difference in parental Infant-Directed Speech (IDS) is limited and there is a particular lack of research on fathers' compared to mothers' speech. This study examined the predictive relations between infant characteristics and variability in paternal lexical diversity (LD) in dyadic free play with two-year-olds (M…

Efficient language use involves the capacity to flexibly adjust to varied pronunciations of words. Although children can contend with some accent variability before their second birthday, it is currently unclear when and how this ability reaches its mature state. In a series of five experiments, we examine the developmental trajectory of toddlers'…