Policy makers, practitioners, and researchers have emphasized the importance of supportive relationships between staff and parents in early childhood education settings and schools. Child care staff members can provide social support for disadvantaged parents who often lack social capital and sources of social support. Yet, there has been limited theory to help understand how these supportive relationships emerge and how parents draw resources from these relationships. Further, very few studies examine staff-parent relationships in after-school programs—widely used programs that can provide social support to parents with school-aged children and adolescents. This qualitative study applies concepts from social capital theory to examines 1) how social ties between parents and staff members develop and vary and 2) how parents mobilize these ties for resources. In doing so, we analyze 23 in-depth staff interviews and 48 parent interviews across three after-school programs. We find that a select group of parents develop and activate strong social ties with staff for social support. Strong tie development reflects a distinct social process of rapport building, time, shared experiences, and pivotal moments in which staff members demonstrate trustworthiness.