Presently there is a body of research examining second language acquisition in young children in formal contexts such as the schools and daycares, but few studies have focused on the children’s home. Furthermore, examining how children learn English as a second language in immigrant families is vital since twenty-three percent of the United States’ children are immigrants or are the children of immigrants (Census Bureau, 2011).  Speaking Spanish rather than English has implications for school readiness and achievement. Children who do not speak English must simultaneously learn English vocabulary and grammar, reading/writing skills, and the constructs and content of academic subjects, which could result in academic difficulties (Suarez-Orozco & Suarez-Orozco, 2001). Speaking Spanish children from immigrant families are often seen having language gaps due to limited economic sources or expertise in US.schooling (Kibler, Palacios, Simpson-Baird, Bergey & Yoder, 2016). For many children, siblings are the first peers (Dunn, 2002). In many collectivistic societies, siblings play an important role in other children’s lives. According to Brody (2004), sibling interactions promote language and cognitive skills.  For many African American and Latino families, older siblings are responsible to take care of the younger siblings.  For instance, research conducted on the Polynesian Islands, demonstrated that is very common for older children in the families to take care of their younger ones.  Since older siblings spend a lot of time taking care of their younger siblings, this creates opportunities for children to learn from their siblings. The purpose of this paper is to examine how older children in immigrant families play an important role in their younger sibling’s language acquisition. Specifically, this paper will examine how older siblings model language behaviors and how they informally teach English to their younger siblings at home.