I'd say nothing to your child or son/daughter-in-law.
If your GD is rude to you personally, say something.
Are you ever alone with her? If she misbehaves when in your house, I think you could point out a thing or two.
I'd phrase things carefully though. You don't want to end up having a terrific row with her parents.
I would not have minded if my in-laws or parents had told off my children if they behaved badly. However, modern parents might be different.
Last three letters new game Novembet 13thr
Speculation: Who Will Be In Burnham's Cabinet?
Swimming pool was more like a talking pool!
