My Mothers mom (my grandma) passed away when I was 10 years old. I only met her a couple times but she did have a sister (My mothers Aunt). I faintly remember having christmas with them one time as a child and they were not warm or friendly like family gatherings (especially christmas) usually are and I have not seen them or spoken with them since then. (about 15 years). When I was going through my guest list with my mother the other day, she was upset that I did not include her and when I advised my mother of my reasoning ( I don't see them or even know them for that matter) My mother advised me that it would be rude not to invite her, regardless of whether I know her or not, as she is my grandmas sister. I am already pushing 300 guests right now and have over 100 close family members already being invited. AND there is a kicker. this particular aunt has 3 kids all of whom I have only met once in my life, and of course my mother is requesting that I invite each of them and their +1 as well. Do you feel that it would be rude for me to push back on my mothers request and not invite them?