Purpose: Siblings of individuals with disabilities provide the most long-term care for an individual with disabilities, yet research on their experiences is limited. A majority of previous research focuses on young siblings from a parent's viewpoint. The purpose of this paper is to investigate the effects of having a sibling with a disability and behaviour described as challenging from adult siblings' perspectives. Design/methodology/approach: Six adult siblings of individuals with intellectual disabilities and behaviour described as challenging were interviewed about their responsibilities pertaining to their sibling, family relationships and the support that had been provided. The study used semi-structured interview methodology based on interview questions from previous research. Findings: Siblings described a multifaceted impact on their lives. They attributed aspects of their career choices, personal characteristics and family dynamics to having a sibling with a disability and behaviour that challenges. Siblings stressed the inadequate support that they have received throughout their lives. They are, in a sense, the invisible carers for their sibling but they are perceived by society as just a sibling. Siblings described an optimistic perspective on their lives, even though they expressed the difficulties that they have faced. Research limitations/implications: Due to the recruitment process and limited demographic of the participants, the findings may not be generalisable to the general population of siblings of individuals with disabilities. Further research should focus on a broader population. Practical implications: This study reinforces the need for more support for siblings of individuals with disabilities in childhood and in adulthood. Originality/value: This paper provides perspectives of individuals that have not been fully represented in previous research.