My sister's children (preteens) behave badly. They are deliberately rude and swear and no one pulls them up on it. The parents seem to find it endearing and there's a lot of tension generally in the family. My mum and dad tread on eggshells and it's become the elephant in the room.
It's at a point where I don't want my children to be around them. My children don't use bad language and would know not to repeat. But they will go out of their way to do things like say Father Christmas is not real etc.
It brings up a Christmas dilemma though as we're all supposed to be having a family gathering over several days which I do want to be a part of.
What do I do? Just ignore it and prep my kids beforehand? Or pull my nephews up on their behaviour.