AITA for not wanting to see my husband's sister on Christmas?

Obviously family dynamics are complicated and compromise is an important part of a healthy marriage.

My(31F) husband(35M) has one sister(38F), whose family of 6 lives with their mom. For the first 5 years of our relationship/ marriage we spent time with his family on Christmas day, often most of the day. I have been clear from the beginning that once we had kids, I expected us to enjoy Christmas morning at home (grandparents welcome if they want). Last year, our daughter's first Christmas was at home and we celebrated Christmas at his mom/ sisters on Saturday. This year, that is also the plan.

At some point, he argued that we should still make it over there at some point, like for Christmas dinner. I am not interested in that. From the beginning of the relationship his sister has been mean girl passive aggressive to me. At some family events she would full silent treatment me, not acknowledging a question asked directly to her from a foot away. I'm a sensitive person by nature (so is my husband), and her mean behavior really affects me. He told me he's learned to just ignore her behavior, and i should too.

I believe I should no longer have to spend holidays with people who make me feel badly intentionally. His mom makes me feel bad with mean comments too, but I believe they are usually unintentional, so I excuse them.

We agreed on this, and think the Saturday after is a fair compromise. Then we got invited to my sister's house for a gift exchange on Christmas evening. I checked with him, and we both wanted to go. I told him it didn't change my mind on going to his family's, and he said that was fine and didn't bother him.

We agreed on the Saturday plan in the summer to give his mom plenty of time to prepare. She was disappointed, but ok with it and planned a family wide trip out of state for early December which we attended and enjoyed despite me feeling badly about some comments from sister on the trip.

This week his sister heard from my sister about the Christmas plan (they church together), and told his mom. After a phone call from his mom, he insists he never liked our plan and it's important to him to go to their house on Christmas day, for at least an hour.

I said no, your sister is mean to me and I don't think I should have to spend time with someone who is mean to me on Christmas. He said that's just what you do for family, you go whether you have a good time or not. I don't agree. I'm happy to sacrifice all day Saturday there, but actual Christmas day, I think should be only for people who care about you and your feelings.

He said he can just take our baby alone, which i think is ridiculous. I don't think I should have to be alone on Christmas Day to accommodate someone who is mean's feelings over mine. As stated above, his mom is welcome at our home on Christmas, and while she insists it's important to her to see us and her grand baby on Christmas Day, she is not willing to come over. It's only an option if we go to her.

Husband agreed springing this on me three days before Christmas was inappropriate, so it's off the table for Thursday, we agreed to talk about it for next year.

I know Christmas isn't all about me and my feelings, but I don't know how to feel better about agreeing to this. I don't want the stress on Christmas Day, and I don't want my kid's Christmas Day to include that behavior either. But my husband also deserves a say on his Christmas. He will not confront his sister about her behavior so mending fences isn't really a possibility, it's just up to me to suck it up. My family has only ever been kind, gracious and supportive of him, and he genuinely enjoys their company as friends.