Hithere
So your son and his sister do not get along- it is up to them to address it and fix it, nothing you can do there
I would stop trying to get both siblings and their kids in the same room
As for her aunt being in the house at the same time their kids are - sensitive subject
Yes, it is your house and if she is there, the parents can tell you she cannot be there
At the same time, if the parents don't want their kids because they don't trust her - it is their prerogative to search for a different babysitting arrangement
Too much missing info here - why do they think your daughter is not trustworthy? What happened?
Small kids love people because they have a good time, give them candy, and do fun things, etc
It doesn't mean, generally speaking, those adults are safe people
I do not get involved between my son and his sister. I do not try to get them all in the same room. I am on pins if one of them is here and the other one turns up.
My daughter is not unsafe around the kids.
It was a silly fall out over a misheard conversation amongst my Daughter and DIL friendship group.



