Consistent with contemporary theories related to the well-being and adjustment of children, the Ontario Child Welfare Transformation policy suggests that researchers and practitioners consider multiple levels of analysis when attempting to understand, prevent, and respond to childhood adversity. By examining the phenomenon of parental stress among child welfare cases, the present study sought to integrate family, child, and service-system levels of analysis through a family-based standpoint of investigation. A sample of 135 families was selected from three Children's Aid Societies in southern Ontario. Using hierarchical regression, we found that child developmental milestones (4-47 months old) and child behavioural and emotional strengths (48 months +) were associated with parental stress, accounting for variance beyond family-level predictors. Children of parents who were stressed had higher health and social service costs, though this trend did not apply for stressed parents themselves. Theoretical and applied implications are discussed.