LAUSR

Childhood genetic conditions impact not only the child who is diagnosed but also the day‐to‐day lives of all members of a family. However, our understanding of the perspectives and needs of unaffected adolescents in families affected by rare genetic conditions is limited. To address this gap, we conducted semi‐structured interviews with 10 participants aged 14–20 years, all of whom had a sibling with a rare genetic condition. An interpretive description approach was used to develop a framework that described how participants' experiences of having a sibling with a rare genetic condition shaped the formation of their identity. This experience influenced identity formation both directly, and indirectly through four other phenomena: (1) normalization, of both their own experiences and their siblings' differences; (2) knowledge seeking, regarding their sibling's condition and what uncertainties remained; (3) caretaking, which limited some opportunities and was associated with uncertainty around the future; and (4) social experience, including their relationship with their affected sibling, with their peers, and with the rest of their family participants felt that they were isolated and lacked appropriate supports. The results of this study can help to inform a family‐centered approach to genetic counseling and highlight the importance of tailored supports for this population.