Choosing My Cat Over My Half-Brother: AITA for Making a Stand?

Some families keep score with money, others with grudges, and this one apparently keeps it with birthday schedules and a cat named Claire. The moment OP decided to skip their half-brother’s party and throw an extra-long celebration for their cat, it turned a simmering betrayal into a full family fire drill.

Here’s the messy backstory: OP (18) used to get along with their half-brother (19) even though their dad’s cheating created the whole situation. Then OP found out the half-brother was sleeping with OP’s girlfriend, and the fallout was immediate, blocks included. Now, because the half-brother and Claire share the same birthday, OP usually does two parties, one for each. This year OP chose Claire, with mom, aunts, and friends, and refused to reconcile with the man who enabled all of it.

Now OP’s dad is calling him a “bad brother,” and one aunt thinks OP went too far.

Original Post

I(18m) used to have a relatively good relationship with my half-brother(19), despite the fact that my dad cheated on my mom with his mom with the excuse that he thought my mom would never be able to 'provide a child.' I never blamed my half-brother for it and we got along reasonably okay up until I found out he has been sleeping with my then-girlfriend(18). Blocked and haven't talked to him for four months now.

My cat and my half-brother have the same birthday so over the past several years I would attend my half-brother's birthday party in the morning and throw my cat's birthday party afterwards. Yesterday though, I decided to have an early, extra long party for my cat instead with my mom, aunts and friends.

They all adore Claire. I didn't go to my half-brother's birthday, which caused my dad to call and say that I was being a bad brother for not forgiving my half-brother and reconciling.

So I told him that my half-brother was the one who betrayed me and that I am not interested in conciliation. He asked me if my cat is more important so I said yes, and that I would always choose my cat over him.

Now I have three aunts. All my mom's sisters, all hate dad for cheating on her.

But one of them said I was a bit too harsh on him. Was I too harsh to my father?

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That “already tipped” moment reminds me of the Domino’s debate, where a Redditor claims they tipped twice.

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The usual routine falls apart when OP skips the half-brother’s morning party and goes all in on Claire with mom, aunts, and friends instead.

That’s when dad calls to accuse OP of not forgiving the half-brother, even after the girlfriend betrayal and the four-month no-contact.

Meanwhile, mom’s sisters are already furious about the cheating, so OP’s decision lands in an emotionally charged house full of opinions.

Then one aunt drops the controversial take, saying OP was “a bit too harsh,” and suddenly the birthday drama is about more than a cat.

Share your thoughts and experiences in the comments section.

OP might be “choosing a cat,” but the real question is whether anyone in that family can stand the truth about what the half-brother did.

For another inheritance fight, see why someone refused to share money with their childfree sister after grandpa’s will.