Christmas crossover with exwife?

So my boyfriend of 1.5 years just managed to finish the Christmas discussions with his ex. His daughter (7) will be around from midday to 6:30 pm, then he will bring her to his ex - they will drink punch at a campfire at her house together as habdover time and then he will come to my parents. He would be there around 7:30-8pm.

My parents would like to start earlier and to have me there - im not sute what to do. The ex is a real pain in the ass and the daughter rather difficult right now - it would be easier to just stay at my parents and wait for him. My boyfriend would love for me to celebrate with him and the daughter.

There is no right and wrong - just dunno what to do.