The home-language environment of children from language minority immigrant families, especially in much need for study (Snow, Bums, & Griffin, 1998; Tabors, 1997;). I investigated the home-language environment of 49 Spanish-speaking families and their bilingual children by focusing on mother-child language interactions during two literacy-related activities; a book sharing and a homework. I used several sources of data; interviews, standardized tests, observations, and language interaction throughout 3 different studies. In Study 1 I described the language used between mother-child during the activities. In Study 2 I looked at the relationship between mothers' language-use and the children's bilingual vocabulary scores. Finally, in Study 3 I investigated the implications of bilingualism closer; through the detailed description of the language environments of four mother-child dyads with their four children representing four different levels of bilingualism. Study-I. Ifound that mothers took a "teaching approach" on sharing the book with their children by scaffolding their interpretation of the book's content and by the large variety of talks they produced during the book sharing. Strategies previously found in English monolingual families as strong predictors of literacy skills (e.g., explanations), were also found in this sample of bilinguals. The mother-child language interactions were different between the two activities; helping the children with the homework (with English instructions) seemed to be more difficult for these mothers than sharing the book. Study-2. I found that English vocabulary is influenced by multiple home-environment factors and many of the factors influencing English vocabulary positively also influenced Spanish vocabulary negatively. Spanish language-use factors influenced Spanish vocabulary positively. A regression analysis indicated that the mothers' labeling questions used during the book sharing, in Spanish, was significant predictor of vocabulary in both languages, Spanish and English. Study-3. The dyads' talk in four families indicated that the participants' differing levels of proficiency in Spanish or English influenced the mothers' quality of language input during the activities, especially during the homework. Overall these studies demonstrated the complexity of these bilinguals language development and the tremendous implications that their home-school language environments had in mediating the quality of mother-child language interactions, thus, influencing the children's language development. (author abstract)