“I would not change [my] sibling for the world, maybe the world can change for my sibling”: The experiences of adult siblings of people with developmental disabilities

The sibling relationship is complex, unique and important. When one sibling has a developmental disability, siblings can be important sources of care, support, advocacy and friendship for one another. We drew on online survey data from 456 UK adult siblings of people with DD. Siblings provided written responses to a prompt about their sibling experiences (> 80,000 words). These data were analysed using qualitative content analysis and organised using the Siblings Embedded Systems Framework (SESF). The SESF helps us to consider how complex interacting mechanisms and factors surrounding siblings, families and wider systems at a local, national and international level, can influence siblings' outcomes, experiences and relationships. Overall, siblings shared a range of experiences related to their: mental health and wellbeing; personal characteristics; sibling relationships; intra‐familial experiences; caring experiences; experiences accessing support services; community experiences; and views on the discrimination and ableism that their disabled siblings experienced. Siblings reflected on the interconnected and dynamic nature of their experiences. We found the SESF to be a useful way of presenting an account of the data overall, as well as to explore the impact of societal factors on siblings' experiences. Siblings' structural, political and social contexts impacted their personal lives. Please refer to the Supporting Information section to find this article's Community and Social Impact Statement.