BACKGROUND: Adolescent siblings of children and young people (CYP) with cancer are at increased risk of psychosocial difficulties, yet many remain overlooked and unsupported. This project aimed to explore the experiences and perceived needs of adolescent siblings of paediatric oncology inpatients to inform service improvement recommendations for sibling support. METHODS: Semi-structured interviews were conducted with 10 siblings of CYP previously admitted to a paediatric oncology ward. Interviews were transcribed verbatim and analysed using reflexive thematic analysis. The findings were reviewed in consultation with staff and used to identify pragmatic/feasible recommendations for improving sibling support, organized using the three-tier 'Pediatric Psychosocial Preventative Health Model' (PPPHM
Families, Systems & Health, 2006, 24, 381). RESULTS: An overarching narrative of siblings wanting to feel part of the cancer journey was found, including their family's experience on the ward, with three key themes: (i) "what about me?": overlooked and unseen, (ii) "always changing, never knowing": the challenge of uncertainty and (iii) "let me be part of it all": togetherness, communication and connection. These findings informed sibling support recommendations. Such recommendations included providing psychosocial screening, resources and opportunities for family time/communication and developmentally appropriate information to all siblings (universal support), monitoring psychosocial difficulties, siblings having someone to talk to and fostering family and peer connection for siblings requiring additional support (targeted support) and offering one-to-one psychological support and family therapy for persistent and/or escalating distress (clinical/treatment support). CONCLUSIONS: Based on the experiences of siblings, a range of sibling support recommendations have been identified. Implementation and evaluation of these recommendations are warranted.