AITJ for turning my brother’s gender reveal into a “silent disco” after they banned kids from the party?

My brother (29M) and his wife (27F) are expecting their first kid and decided to go all out for the gender reveal. I (31F) have two kids (4M & 7F) and we’re all pretty close, or so I thought. Last month, they sent out these super fancy invites for the reveal party. think custom cupcakes, balloon arches, the works. But the invite said “adults only, strictly no kids.” Like, bolded and underlined.

I texted my brother to double check, thinking it was a mistake. Nope. He says they want a “classy vibe” and “grown-up fun,” and apparently kids would “ruin the atmosphere.” He made some snarky comment about my youngest being “a handful.” I was honestly hurt, but whatever. your party, your rules.

Here’s where things get spicy. My parents were also annoyed, since they wanted all their grandkids there, and a couple other family members actually declined to come because of the ban. So the day of the party rolls around, and my husband says, “Fine, let’s go, but let’s make it fun for us at least.” On a whim, I grabbed my wireless headphones and made a playlist for myself and my husband (think: Baby Shark, Cocomelon, and other kid chaos music). At the party, we put on our headphones and started quietly dancing and doing our usual “parent chaos” moves. My sister-in-law’s friends thought it was hilarious and a few people actually joined in, making it a whole “silent disco” for the parents who had to get sitters.

My brother LOST IT. He pulled me aside, said we were “mocking his big moment” and “making a scene.” I said, “Sorry, we’re just making the best of a weird situation.” He thinks I disrespected the event and is still mad, texting me about how I “ruined the mood.” My parents are split. my mom thinks it was funny, my dad says I should’ve just gone with the flow.

TL;DR: Brother banned kids from his gender reveal. I brought headphones and danced to kid music with other parents as a joke. He says I ruined the party. Am I the jerk?

So, AITJ for bringing a “silent disco” vibe to a kid-free gender reveal because I felt snubbed?