Just have a nice day at home and let it go.
4 years ago, when I had ds1 2 yrs and ds2 6 mths, I did a big family Christmas, my family, In-laws, SIL and her family plus her husband's parents, as he's an only child.
Christmas has always been an issue, with my parents being the most likely to invite everyone and also the most easy going when it wasn't their "turn" and MIL getting terribly upset if arrangements didn't suit but never doing it herself.
Christmas Day came, I did dinner for 12, missed my boys opening most of their pressies, MIL complianed I didn't talk to her enough - strangely becuase I only really spoke to people who were in the kitchen.
Few days later is my DH birthday and I invited them to lunch. She refused to speak to me all afternoon, even when spoken to, made a excuse to leave early and we haven't seen them since. My boys don't even know they have another set of grandparents, but that's another story.
It really bothers me how much pressure is put on one day to be perfect (like weddings).Enjoy the day however it goes and promise not to be like that towards your DIL. I've already decided I'm going to the Lakes for Christmas the fist year we're not invited to have Christmas with our sons. Can't wait