Anvilhead, I always look forward to your no-nonsense advice. Thank you.
The kids already have a place to stay with my parents and her ex-husband. But my parents don't have official custody, my sister just drops them off whenever she feels like it, which ends up being 3-4 times a week. However, my dad is legitimately concerned that my sister's income won't be enough for her to rent a safe place for the girls.
Anyway the girls are 14 and 11. The eldest one barely speaks to her mother, but we don't know if it's just normal teenage angst or something else. We try very hard not to speak ill of their mother in front of them, although there have been a couple times where we've caught them listening in or we've slipped when we didn't realize they were within earshot.
But they're really awesome, amazing kids. I like to think that my sister reserved her very best behavior for them before she lost herself nine years ago.