Objective This study investigated mother–child discrepancies over perceptions of who is responsible for spina bifida (SB) medical tasks in relation to family conflict and medical adherence. Method 140 youth with SB and their mothers completed questionnaires regarding who is responsible for specific SB medical tasks, family conflict, and medical adherence. An observational measure was also used to assess family conflict. Results Although children viewed themselves as more responsible for medical management than mothers did, mother–child discrepancies were not associated with family conflict or medical adherence. Interaction effects revealed that adherence was better when family conflict was low and when parents were responsible for medical tasks. Conclusions Parental involvement in SB medical care is essential for optimal medical adherence during adolescence. The presence of family conflict also plays an influential role on SB medical adherence. Future research should evaluate the relations between discrepancies, family conflict, and medical adherence across time.