This two-part dissertation investigated the home language experiences and language development of 35 toddler-aged children from low-income Mexican immigrant families. These children represent a rapidly growing demographic in the United States. Because early language abilities are closely linked to later academic success, understanding the characteristics of the early language learning experiences provided in the homes of Mexican immigrant children is a foundational step to supporting their strengths and needs prior to formal school entry. In the first study of this dissertation, semi-structured interviews were conducted with the children’s mothers regarding the everyday activity settings of their young children. Degree of maternal acculturation was also assessed. Commonalities and variations in mothers’ values, beliefs, and practices regarding language teaching and learning were revealed. The commonalities included attention towards children’s early behavior and social skills, collective child-rearing practices, emphasis on the family unit and Mexican identity, and support for Spanish-English language learning and educational success, among others. A limited number of variations were also found to be associated with mothers’ affiliation with Anglo-American culture. In the second study, naturalistic recordings of the toddlers' language input in the home were analyzed in-depth to describe features of the quantity and quality of the input to which children were exposed. A wide range of variability in children’s quantity and quality was found. In addition, the relative amount of Spanish and English spoken to children was determined. Spanish was the primary language used with children, although English was also used in most homes. Children’s productive vocabulary in both languages was further measured contemporaneously; total vocabulary size ranged widely across children. There were no associations revealed between the characteristics of children’s language input quantity and quality and their productive vocabulary, although quantity and quality were related to one another. Implications of both studies to early childhood researchers and practitioners focused on early language development, including speech-language pathologists, are discussed. / Communication Sciences