I heard a story on public radio last sunday about cases such as a 14 year old girl who was basically held captive for four years at a reunification therapy camp with her verbally abusive mother. Her mother had convinced a judge that her father had alienated her against her mother. the show is called Reveal and the report is called Bitter custody https://www.revealnews.org .
I've visited a residential foster care home where the clients came to them with more trauma than they ever experienced while there. It was mostly a case of things not being as helpful than they could have been, or at most, re-traumatizing to the residents.