Teen wants to exclude autistic stepsister from birthday; mom calls her 'uncaring brat.'

"AITA for not wanting my autistic sister to come to my birthday party?"​​​​​​

I (15F) am turning sixteen soon and I’m having a pretty big party to celebrate. I have a stepsister (16F) who is autistic. She is fairly high-functioning but very spoiled and throws tantrums whenever she doesn’t get what she wants. When I was little, she would always ruin my birthday parties so I stopped having parties with my mom’s family. I usually have parties with just my dad's family and my friends.

This year, I’m turning 16 so I’m having a bigger party which my dad is mostly paying for but I’m inviting my mom, stepdad, stepbrother, and half-siblings (13M and 11F). I’m having a party with about 90 people and over the weekend my grandma is gonna take me and some of my friends and cousins to their cabin in the mountains. I do not want my stepsister to come to the party or to the cabin.

I know she’s going to ruin it. She gets jealous whenever I get anything and my dad is planning to gift me my dream car at the party so I know she’s gonna throw a tantrum. She always steals the attention from me and I just don’t want her there. I’m not inviting her to the cabin either because it’s just for my cousins on my dad’s side and my friends. I’m not that close to my stepsister.

Besides, we’re going to hike, boat, ride horses, and do other outdoor events that I know my sister can’t handle. She’s gonna start crying if we try to go on the water and she can’t walk further than half a mile without getting tired. Yesterday my stepsister told me that she’s really excited for my party because it’s at the zoo and she loves it there and she has never stayed in a cabin before.

I told her that she was not invited and she started crying and ran to her room. My mom called me an uncaring brat for not inviting her and telling her so bluntly. She said that her and my stepdad aren’t coming either if she’s not invited. I don’t think I’m the AH because it’s my party and I don’t want her to ruin it.

The internet weighed in.

bergreen wrote:

As an autistic person myself, let me be the first to say NTA.

Your birthday party is about you, not someone else.

That said, with comments like these:

"She is fairly high functioning but very spoiled and throws tantrums"

it sounds like you have a lot to learn about autism. Obviously, your step-sister is not your responsibility, but learning would make your life (and everyone else's life) a lot less difficult.

Also excluding a close family member will likely cause lifelong problems. I don't think that's your fault, just want to prepare you for the reality. Yes I know autistic people can be spoiled too, thanks. Someone else already said it, your comment isn't new so please don't post it.

theitguy1968 wrote:

NTA. It is your party. Is it a great loss if your mum and stepdad are not there as well?

Have a great birthday.

whatever_787 wrote:

I’m not sure your sister is very high functioning. I am high functioning and don’t spit on things etc. Maybe her parents need to set up some ground rules she has to follow.

aGirlySloth wrote:

If for the past few years you’ve kept your birthday separate cause of your step sister, you should have kept it going for this one. I don’t think you’re T A for not wanting her there based on history but you can’t invite everyone except her.

I think your mom is T A for not being more understanding of your feelings and that it’s kept you from celebrating on that side of the family. At this point, it looks like she’s reaped what she sowed with this whole situation. Best outcome would be that your mom/step dad don’t come so that she won’t ruin it. I don’t think you’re selfish or a brat. NTA overall.

FutureDPT2021 wrote:

ESH. You can't invite everyone (your mom, step-dad, step-brother, half-siblings) without inviting your step-sister, because who is supposed to stay with her/it is very personal to exclude one minor from your entire family. Your mom/stepdad/his ex-wife for spoiling her, not teaching boundaries, etc.

And your step-sister for not working on social etiquette, if she is as "high functioning," as you say. I completely understand the cabin situation, but the party was a bit much to single her out from attending.

OP is mostly voted NTA here, although it seems like she needs to figure out a more sustainable way to navigate this dynamic in the future.