<p>Pediatric acute-onset neuropsychiatric syndrome (PANS) is a relatively new diagnosis, characterized by an abrupt and dramatic onset of obsessive-compulsive disorder together with neuropsychiatric symptoms. This sudden onset of symptoms that occurs within 24–48 h presents tremendous challenges for the affected children and their immediate family members. Currently, research on the experiences of siblings of children with PANS is lacking. This study explored siblings’ perspectives on living with brothers and sisters with PANS, and their perceptions of own ability and available resources to manage challenging situations. Nine siblings of children with PANS, aged 10–17 years, participated in semi-structured interviews. Informed by Transactional Theory, a combined deductive-inductive approach to qualitative content analysis was used for analyzing the data. The findings illuminate that PANS has considerable impact on the lives of healthy siblings who experienced fear of aggression and unpredictability of their siblings’ behavior; they felt that their basic needs as well as social and emotional needs were often neglected. The results also showed that siblings lacked formal knowledge about PANS and had only a limited number of strategies to cope with stressful situations. However, peers in similar situation were a source of emotional support. Practical implications include the need for development of community-based, family-centered support programs to reduce the impact of PANS on healthy siblings’ well-being. Directions for further research are outlined.</p>