Research suggests that school-based parent networks have significant benefits for children's education, yet scholars know very little about how such relationships form and develop over time. This study uses interview and survey data with elementary school parents in predominantly low-income Latinx communities to examine how parents meet one another; how deeper, more trusting relationships develop; and how the size and quality of parent networks change over time in the presence and absence of a family engagement program. Interview data suggest few and infrequent opportunities for parents to meet one another, which makes building relationships characterized by trust and shared expectations more difficult. The quantitative results show positive short-term effects of the program but differential effects over time.