I just got a text from my SIL (on DH's side) saying "my dad is coming tomorrow, let me know if I need to bring an extra chair" I found this to be a little on the rude side. First of all, he isn't even part of our family and I've never met this guy before and I wasn't planning on anyone else but DH, his parents, and his brother/SIL. I am all for getting everyone together for the holiday's, and he is more than welcome to come, but asking would have been respectful and much appreciated.

I think it's common courtesy to ask the host before bringing an extra guest to their home. What are your thoughts? Rude? No big deal either way?