Objective: Mental health service providers often have limited or problematic understanding of parents support needs or experiences and family relationships. Moreover, the impact of family life and relationships for mothers with mental illness, and whether these relationships are experienced as positive or negative, have been largely underinvestigated. This article aims to increase understanding about the complexity of family relationships and support for mothers. Findings may be useful for services when considering family involvement, and for how to better meet the needs of mothers with mental illness and support their recovery. Method: Semistructured interviews were conducted with 8 mothers with mental illness and 11 mental health service providers. This article presents a grounded theory analysis of the complexity of family relationships and support for mothers with mental illness. Results: Family relationships of mothers with mental illness can be complex, potentially difficult, and challenging. Problems in relationships with partners and families, and experiences of abuse, can have harmful consequences on parenting, on mothers and children s well-being, and on the support mothers receive. Conclusions and Implications for Practice: This project highlights a need to recognize and work with positive aspects and difficulties in family relationships as part of mental health service provision. Policies can be reviewed to increase the likelihood that mental health care will combine family-sensitive practice with practice that acknowledges difficult family relationships and experiences of family violence in order to maximize support to mothers with mental illness and their children.