Service engagement is critical when working with children and families experiencing chronic adversities because of their socially marginalized status. Further, sociodemographic disparities exist in service engagement within service systems including Community-Based Behavioral Health; likely in part, a result of structural issues driving unresponsive service systems. Despite this knowledge, a large proportion of the family engagement literature continues to be approached through a deficit-based and family-centric lens leaving out important systemic considerations and furthering health inequities. Drawing from a Socio-Ecological Framework (Stokols, 1996), this study focuses on exploring the value of peer support providers (PSPs) to understand how sociocultural responsiveness functions under this service model. Individual interviews and focus group data were collected from both families and PSPs. Thematic analysis (Braun & Clarke in Qualitative Research in Psychology, 3(2), 77-101, 2006) was utilized to code and synthetize the data collected. Findings highlight the importance of capitalizing on meaningful and trusting relationships to foster family engagement in services. These findings solidify the understanding that family engagement is a function of crucial relationships between family, provider, and systems. This work also illustrates how PSPs organic embodiment of sociocultural responsiveness through cultural humility is an avenue through which family engagement can be sustained. [This is the online first version of an article published in "Prevention Science."]