This document discusses family dynamics in sexually abusive families. It notes that these families often have a single parent, usually the mother, who became a parent at a young age. The parents also often have histories of substance abuse, incarceration or mental illness. There is frequently a past history of childhood sexual abuse or other trauma in the parents. The families also commonly experience substance abuse, domestic violence and a lack of understanding of roles and boundaries. However, the document cautions against making assumptions, noting that family characteristics alone do not determine sexual abuse.