["Bioethics, Volume 40, Issue 5, Page 482-490, June 2026. ", "\nABSTRACT\nScientific advancements offer new possibilities for developing novel treatments for children with monogenic neurodevelopmental disorders (mNDDs), targeting the underlying effects of their condition. Although, in qualitative studies, parents of children with mNDDs have predominantly positive attitudes towards the development of novel treatments, a few parents express concerns about whether treatments could change who their child is. Existing literature on personal identity, including literature on how personal identity is affected by medical (neuro‐)interventions, can assist in clarifying these concerns. This paper provides an analysis of interview data on perspectives of parents with children with mNDDs (STXBP1‐Related Disorders and Kleefstra Syndrome) on the impact of novel treatments on their child's identity. We identify four sets of concerns, about whether treatments (1) enable children to develop their self, (2) alienate children from their true self, (3) disrupt children's relational identities, and (4) defy children's horizontal identities. While parents hope that treatments will help children flourish, some worry that treatments may alienate children from their self or alter children's personal characteristics which are meaningful to caregivers, thereby disrupting family dynamics. Others fear treatments may produce stigma by perpetuating the narrative that children need to be “fixed”. This analysis helps to understand the ambivalence some parents express when considering their child's participation in clinical trials. For clinicians and researchers, it is essential to discuss parents' concerns about impacts of treatments on their child's identity (if present) when deciding on the child's participation in clinical trials, and to monitor children for identity‐related effects of novel treatments.\n"]