Purpose: The experiences of parents caring for the complex care needs of children with rare neurodevelopmental disorders are not well understood. Parents struggle to meet their children's medical, behavioural, and social needs within and across health, social, and family systems. The purpose of this study was to explore the parents' experience of caring for medical and social care needs for children with rare neurodevelopmental disorders. Methods: Hermeneutic phenomenology was used for the data analysis. Fifteen parents participated in semi-structured interviews. Results: Interpretive analysis revealed four insights: (a) difference in children's behaviours and disease manifestations led to misunderstanding and vulnerability within social domains, (b) social taboo and stigma were experienced with rarity, (c) fragmented disconnected care from health and social systems impacted families, and (d) incomprehension from friends and family occurs when managing daily care. Conclusion: New interpretations and increased understanding of parents' experiences are required in supporting parents caring for children with complex needs. Understanding parents' experiences could reduce social isolation and exclusion, and mitigate appropriate and supportive practices and services within and across medical, social, and family systems.