My stepdaughter does Thanksgiving every other year with us, but Christmas is split in half and Christmas morning is traded off.
I have to say that this year it was particularly hard on her. She did Christmas Eve with my Hubby's mom's family and Christmas morning with us. She was up late so she could "fully celebrate" Christmas Eve.
She only had time to open her gifts before we had to pack them up so she could go to her mom's. At her mom's she opened more gifts and then stayed up late playing. The next morning she was back with us for MORE Christmas with more family. By that time she was exhausted, crabby and not in a Christmas mood at all, even though she was showered with gifts.
In all honesty I can see that the person who missed out on Christmas the most was HER. She was tossed back and forth between the families because everyone wanted to "fully celebrate" it with her. On Sunday she BEGGED to just "be left alone with her toys." The poor child can barely remember what happened at each house. And she's eight years old.
After seeing her so tired and NOT EVEN EXCITED at opening more gifts (what child is not excited to open gifts?) I can see the side that would agree that maybe she should spend Christmas day with just one parent. She was so sad to leave her newly opened gifts, even though she was going to open more presents and have dinner and family time with the other side. I can see that she might have been happy to wake up, relax and enjoy the day in her pjs while playing with her new toys like we did when we were kids.
I understand that your side of the family has the big party with all the kids and I'm sure you'd miss her a lot if she weren't there. Since she is going to be seven next year, maybe you should as HER what she wants to do, as well as discuss options with your entire family so she can be present. My husband's family saw how tired she was and has graciously decided to celebrate "Christmas to the max" on a day other than Christmas next year so she can be there the whole time and enjoy all of her toys.
We are going to discuss with her what she wants to do next year and try to remember that Christmas is also about what she wants. She may want a relaxing Christmas, and if that means we give her up for the day, then that's what we do. If she wants to split the day, we'll do that too.
Hope that helps.