With the on-going presence of a chronic illness, daily immunosuppressive medications, and the need for continuous medical supervision, pediatric transplant recipients face considerable psychosocial stresses. Treatment nonadherence is a major issue in pediatric transplantation and can lead to increased rates of hospitalization, rejection episodes, graft loss and death. An online peer support mentorship program (iPeer2Peer) is proposed as one intervention that could enhance patient care management, increase treatment adherence, reduce social isolation and improve health outcomes for this highly vulnerable population. The proposed trial will determine 1) implementation outcomes of the iPeer2Peer intervention in terms of: (a) feasibility and adoption, (b) acceptability and appropriateness and (c) level of engagement with the program, and 2) effectiveness of the iPeer2Peer intervention on improving health outcomes including disease self-management skills, treatment adherence, quality of life, perceived social support, stress and coping.