I 32 (F) have a sister (31) we’ll call her J, is getting married at the end of May. My eldest sister (36) has 6 kids. The oldest 2 girls and 2 boys are to be in the wedding no matter what and her youngest daughter 3 would possibly be in the wedding if my son (4) was up for it. I told her of course he’d love to be in it back in January. Fast forward to February and J is getting iffy on if she’d have my son it now. I told her that of course the wedding would be a bit more fun with out the kids present but if she wanted my oldest in it then that’s what we’d do. I did look into the possibility if my SIL would take both my boys for the weekend if my son wasn’t to be in it but she wasn’t available so no matter what my kids have to come with for the wedding as I don’t feel comfortable leaving them with anyone else for 2.5 days but we’d have a babysitter come with to watch them. Through all of February and March I kept asking my sister what the plan was on if he’s in the wedding and she never gave me a straight answer. Fast forward to last week and she sends a message saying no kids under the age of 5 unless in the wedding. I asked again and she said no he won’t be in it. I decided to ask if my oldest sisters 3 year old is staying home then and she said no. That our niece was still in the wedding. I asked why a 3 year old could be in it and not my 4 year old. She had said before that she wanted to have an even number and now it would be 3 girls and 2 boys. She said that the 3 year old had a better chance of not causing a disturbance in comparison to my son. And that’s when I lost it. So backstory, my 4 year old son has a very severe speech delay. There’s no medical reason for it, just the luck of the draw but unfortunately it’s something that will affect him for the rest of his life and will be many years until he’s fairly on par with his peers. Whenever he gets really excited even I can’t understand what he’s saying. He’s got a lot of energy like any little boy and so I’m not hurt by her thinking he won’t be able to sit for the 20-30 minute ceremony. It’s that she was only thinking of having my niece in if he was going to be in and then decided no he’s too crazy but this 3 year old who also is prone to tantrums because she’s 3 and that’s natural will be fine. So I called her every name in the book basically (not to her face). I told her that her actions felt shitty and called BS. It felt like she was unfairly excluding him and then I hear that my eldest sister actually told J not to include my son saying he’s too loud. If I felt my son was going to ruin the wedding then I wouldn’t let him walk down the aisle because I don’t want to be the parent who’s kid makes a scene on someone’s special day. But my eldest sister who never interacts with my children and has a holier than though personality decided to put into J’s head that my child isn’t fit for the day but her kids are perfect and will have no issues. Both her and her husband are also in the wedding so if something does happen then neither of them can do anything where as my husband isn’t in the wedding and could easily walk away with my son. So yeah, AITAH for telling my sister she’s an AH for kicking out my son yet keeping my niece in her wedding? I was the odd ball out growing up and I see a lot of my personality in my son, and I foresee a lot of bullying in his future unfortunately and my mama bear is coming out because of all this.