How you read the text matters: Caregiver oral reading prosody during shared reading relates to preschoolers' language skills.

Acoustic features of child directed speech (CDS) in caregiver-child conversational interactions are known to capture young children's attention to language input and facilitate language learning. Emerging evidence suggests that caregivers' use of CDS-like features when reading to their child, known as caregiver oral reading prosody, plays an important role in supporting preschoolers' storybook comprehension. Do associations between caregiver oral reading prosody and preschoolers' language extend beyond real-time listening comprehension to broader language skills? Forty-one caregivers read a children's book to their child (ages: 4-5 years) as they normally would at home. The caregivers' oral reading prosody (i.e., intonation and timing features) was examined in relation to children's receptive vocabulary and core language skills. Moderated mediation models then investigated possible impacts of caregivers' broader reading skills and shared reading time on these associations. Caregiver intonation range positively related to child vocabulary, and caregiver inappropriate (i.e., ungrammatical) pausing negatively related to child core language skills. Mediation models revealed that caregivers' broader reading skills indirectly related to child language through oral reading prosody measures. Notably, the indirect effect linking caregiver reading skills to child vocabulary via caregiver intonation range was moderated by shared reading time, with the strongest effects among dyads reporting less shared reading engagement. Findings illuminate caregiver oral reading prosody as one factor linking caregiver reading skills to child language, with particular relevance among families of caregivers with reading difficulties and for those with limited shared reading opportunities.