I couldn't quite decide where to put this, as i think my sister was being ridiculous and a Super SS, but I don't think it merits its own thread.
Last week, on Wed or Thurs (so just a few days before Christmas) Sis said that she's organizing Christmas dinner, and is frustrated because "nobody wants to do Christmas" ie everyone already has plans

I talked to DH and we decided that we will come over instead of just hanging out at home with the kids.
Sis then called to invite us to spend the night on Christmas Eve so we would all wake up together. She was annoyed at Bro because he wasn't coming--he and his fiancee went to visit her folks. I said no way. I don't want to lug my family of 5 over and sleep on the floor on Christmas Eve.
Next idea was that just the kids could spend the night. Ummm, no. My kids are going to wake up in their own beds on Christmas morning. And they're sure as heck going to be spending Christmas Eve and Christmas morning with me and their dad.**Bonus SS points because this is Baby's first Christmas. I told Sis that wasn't going to happen all 3 times she asked.
Friday I picked Niece up from school as usual, and when Sis came to pick her up, Sis asked my kids if they wanted to have a slumber party on Christmas Eve. The kids got all revved up and excited, and I got to be the Evil Dream Destroyer
tm. We left immediately, and as I was wrangling my kids out to the van, I let Sis have it. I may have made a comment about smacking her upside the head if she tried that male cow excrement again.
Saturday Sis and I were talking again. This time her plan was that we would bring all of our gifts over to the house and everyone would open gifts together. As in, not just our gifts for Dad, Sis and niece, but the gifts DH and I got each other and the kids as well. No, not happening. Sis was pouty again and didn't get why I don't want to do Christmas.
Monday, Christmas Eve, I get a call from Sis. It's niece calling to ask if DS, DD and baby can come over and have a sleepover. I asked her to give the phone to Sis, and told her that was a new low and that I would see her Christmas Day at 11:30, and not before.
Christmas Day, we come over and Sis asked what happened to us coming over last night. I ignored her, she sighed and muttered under her breath, and then it was done and we had a fun day. I seriously considered not coming over at all on Christmas day after all the pestering that Sis did, but I had told Dad we would be there, and if we didn't go we wouldn't have seen him. I was ok with that 2 weeks ago when our plan was to have a quiet, low key day, but once Sis started in with her plans, Dad rearranged his plans also. And Sis lives with Dad, so I couldn't really just see him without her as well.