UC Davis

This dissertation investigates the role of the home literacy environment, including shared book reading interactions, in supporting the early oral language development of dual language learners (DLLs) in preschool. It focuses specifically on low-income Mexican American and Chinese American immigrant households, representing the two largest immigrant populations in the United States (Giang & Park, 2022).Three articles are presented in this dissertation. The first article examined the relationship between home literacy practices and bilingual oral language proficiency. Findings revealed that any kind of home literacy practice benefits vocabulary development, regardless of children’s cultural background. Language-specific effects were observed in which literacy practices influenced the vocabulary outcomes in the corresponding language. The second article explored the interactive features of mother-child shared book reading with a focus on the cognitive demand of questions and statements. Cultural differences emerged in the exchange between mothers and children during shared book reading. Chinese American mothers initiated more questions, and children favored different types of responses. Strong contingent interactions were observed in the different cognitive demand levels of maternal and child contributions. The third article examined the relationship between shared book reading quality and home language development. Both similarities and cultural nuances were found between the two cultural groups. Maternal linguistic complexity positively influenced child language output for both groups, while the effect of maternal conceptual features varied by culture. This research contributes to the understanding of how home literacy environment can be tailored to support DLLs’ language development. The findings inform evidence-based practices for parents, caregivers, educators, and policymakers to foster strong language foundations in this growing population.