There is always the urge to say to such people "This is my child. In my eyes their life and happiness has far, far greater value than yours; say, the value ratio of the Hope Diamond compared to a Bucket of Cat Shit. It is not fair, and not entirely rational, but do you really want to push your luck?"

I'm surprised that complaining about the presence of the host's children in their own home didn't get her booted out on her ass, that is truly, truly gauche.