The Research Foundation for the State University of New York (RF SUNY) received a $241,500 Project Grant award from the National Institute of Child Health and Human Development (NICHD) under the Child Health and Human Development Extramural Research program (CFDA 93.865). The award will fund a 2-year research project titled "The Influence of Child-Produced Speech on Infant Language Development." The study aims to investigate how speech from young children impacts infant language development, specifically examining infant preferences for and processing of child-produced speech compared to adult speech, and how these factors relate to vocabulary growth. The project involves three research components: 1) testing infant speech perception and word recognition for child vs. adult speakers, 2) collecting and analyzing a corpus of parent-sibling-infant play sessions to understand the content and complexity of child-produced speech, and 3) assessing whether infant experiences with and preferences for child-produced speech relate to 18-month vocabulary development. The findings are expected to provide important insights into the role of child-directed speech in early language acquisition, which could inform efforts to support language development for infants with varying experiences.