Our findings highlight the importance of fully assessing an adolescent’s family environment prior to making treatment and post-hospitalization recommendations. These data indicate that parental mental health history is a critical risk factor that doubles the likelihood of an adolescent suicide attempt in the year following hospitalization. As a result, assessment of the adolescent’s living situation (e.g., who resides in the home) and the mental health and treatment history of custodial and biological parents should be a regular part of a comprehensive risk assessment and treatment formulation.