OBJECTIVE: Family functioning is associated with adaptation in pediatric illness. This study examines the role of parents’ relationships (specifically romantic attachment) as a predictor of family ritual meaning and family cohesion for parents and their children with cancer. METHODS: The dyads, 58 partnered Portuguese parents and their children in treatment, reported on family ritual meaning and family cohesion at Time 1 (T1) and after 6 months (T2). Parents also completed the questionnaire assessing romantic attachment at T1. RESULTS: Parents’ avoidant attachment, but not anxious attachment, predicted lower family ritual meaning and family cohesion after 6 months. T2 family ritual meaning mediated the relationship between T1 avoidant attachment and T2 family cohesion. CONCLUSIONS: Parents’ avoidant attachment may have a negative effect on family functioning in parents and children. Clinical intervention to address avoidant attachment or/and to promote family ritual meaning may help strengthen family ties.