Re: Irresponsible-ish Grandma
I wouldn't be comfy with it either. I would tell her that we leave the daughter with you, not with SIL's boyfriend. Daughter wants to be with grandma. If you don't want to watch her then don't take her at that time. If it continues she will not be allowed to spend the night.
Happily Married Momma to my two Bambinos & Bambina