Sibling abuse is extremely common, yet child welfare does not provide statutes for its identification and workers are not trained to identify its occurrence. This retrospective study explored adults survivors’ experiences of childhood and adolescent sibling abuse and the family environment that engendered hostile sibling relationships. The varying parental responses from punitive to neglect to collusion with the perpetrator resulted in feelings of helplessness and worthlessness in the victim. Personal narratives of survivors highlight the sibling abusive experience and underscore its devastating repercussions. Recommendations are presented for child welfare to establish sibling abuse as a phenomenon in need of recognition and include siblings in risk assessment.