Peer-delivered health models may hold important benefits for family members, yet their prevalence, components, and outcomes are unknown. We conducted a review of peer-delivered services for families of children and adults with serious health problems. Studies of interventions published between 2000 and 2016 were included if the intervention contained a component for family members. Of 88 studies that were assessed for their eligibility, five met criteria. Familial components included information about the health condition and management, strategies to enhance communication and stress, and the provision of emotional support. Outcomes were largely favorable, including reductions in distress and symptoms of trauma, enhanced quality of life, and positive perceptions of the peer therapeutic alliance. Peer-delivered services for family members may hold important benefits to caregivers however, the research base remains thin. A research agenda to develop and examine these models is discussed.