Research that employs language socialization (LS) as a framework for investigating how Muslim Arabic heritage-speaking children (MAHSC) in the U.S. are socialized into using their heritage language and culture and its implications for Arabic heritage language development (HLD) is limited. Using thematic-based qualitative analysis of data from semi-structured interviews with twelve MAHSC aged 9-13 years old who attend a full-time private Islamic school in Central Illinois, this article enhances our understanding of the role of socialization in HLD and addresses the interplay of language and identity in different social events. Unlike previous LS research that places parents and caregivers as the major socialization initiators, this study highlighted the roles played by other participants outside the inner family circle such as neighbors and Arabic-speaking online gamers. It also revealed that while parents are essential players in the development of MAHSC's pragmatic and linguistic competence, it is the children's awareness and agency that ensure and strengthen such competence. Other findings highlight MAHSC's agency and innovative practices as they negotiate their role and language use in different social events.