Siblings of children with a severe illness diagnosis experience childhood differently than their same-age peers. The purpose of this study was to explore and describe an adult's understanding of their childhood experiences when their sibling was diagnosed with a severe illness. In prior studies, researchers engaged proxies, such as parents, to express the experience of the siblings living with an ill child. Few researchers waited until the siblings matured to adulthood to assess the impact on their lives. The sibling's voice is needed to illuminate their unique experience. Findings from this study may help healthcare providers, social workers, and educators support siblings of ill children. [For the full proceedings, see ED648717.]