oh, no. The women I'm remembering were straight up abusive. One of them was too high to properly bond with the older male child when he was born so she really only wanted the younger girl but she refused to give up custody of him because she could get money out of the grandmother in exchange for being allowed to see him. Kid was like ten showing up to my friend's mom's house with handprint bruises talking about beating hookers and they couldn't get CPS to remove the kid. Fucking sad. I don't talk to that friend anymore for unrelated reasons but last I heard her sister had at least gotten back with the kid's dad and was at least treating my friend's nephew better in front of his biodad.

also idgaf if it is a stress response. It really damages the kids to not have consistent caregivers and to be constantly told that people who were positive influences in their life were actually bad. It's gonna fuck up their ability to set healthy boundaries for the rest of their life. If they can't "ask for help" without fucking a kid up for life then they are an unfit parent. Those women were just uniquely awful people whose kids might have had a better life if mom taking the kids in the break up wasn't the societal default.