Familism may be an important strength and source of resiliency among Mexican-origin immigrant families. Familism has been associated with fewer internalizing symptoms among Latino youth; however, little is known about the mechanism behind this association. This study explored how parental familism may promote parenting behaviors including warmth and support, in addition to family cohesion, and how these factors may impact child internalizing symptoms during middle childhood among Mexican immigrant families. Participants included 104 children between the age of 6–10 (Mage = 8.39) and their primary caregivers (98% mothers; 90% born in Mexico). This longitudinal study utilized a multi-method approach that encompassed parent-report, child-report and observational measures. Data was collected every 6 months through three home visits. Participants completed surveys and video-recorded family interaction tasks. Results demonstrated that parental familism was a significant, positive predictor of observed parental warmth and family cohesion over the course of six months. Further, observed parental warmth and support was associated with less child-reported depressive symptoms six months later. Mediation results indicated a significant indirect effect of familism on child-reported depressive symptoms through observed parental warmth. This study highlights the importance of building on Latino immigrant families’ existing strengths that incorporates families’ values, parenting behaviors, and family cohesion to reduce child internalizing symptoms.