In many aging families, siblings provide important support to adult brothers or sisters with an intellectual disability. However, this presents new challenges that are affected by past relationships and roles, as well as by the current situation and changes brought on by aging. This study aims to explore the ways in which middle aged typical siblings of adults with intellectual disability shape and perceive their role within the aging family. An interpretive phenomenological analysis was used. Data collection was performed through in-depth, semi-structured interviews with 17 middle aged siblings of adults with intellectual disabilities, followed by a thematic content analysis. Four themes were identified: (1) Sibling multiple roles along the life course; (2) The sibling's role in the changing alignment of aging families living with disabilities; (3) A retrospective examination of the sibling's responsibility; and (4) What does the future hold for siblings? Middle aged siblings in the aging family cope with multiple roles, which may elevate caregiving loads. At this point of their life, middle aged siblings come to acknowledge the complexity of their experience that involves love, compassion, stress, and burden at the same time.