I (30M) recently had a minor falling out with my sister (28F), and I’m not sure if I overstepped or if she’s being too sensitive.

She had her first baby two months ago. I’ve been really happy for her — I’m not super into kids myself, but I get that it’s a huge deal for her. She and her husband are both very "baby brain" right now — every conversation somehow leads back to diapers, naps, feeding schedules, etc.

So last week, my girlfriend and I hosted a small get-together at our place. It was mostly friends from work and a few people from our gym — pretty casual, just drinks, snacks, music. I invited my sister and her husband too, but told her upfront it was going to be more of a “chill adult night” and probably not the best place to bring the baby. I assumed they’d get a sitter or just one of them would come.

They showed up with the baby. I was a little surprised but tried to be polite. Within like 15 minutes, the baby started fussing, and my sister ended up sitting on the couch nursing him with a blanket over her, while her husband hovered around awkwardly trying to calm him down. It totally changed the vibe — the music got turned down, a couple people left early, and the rest of us were just kind of keeping our distance. It felt less like a party and more like a weird family visit.

After they left (early, because the baby was fussy), I texted her the next day and said I wished she had respected the vibe of the night and either come without the baby or just skipped it altogether. I said I didn’t want to sound harsh, but it kind of threw off the whole thing and made people uncomfortable.

She replied saying she felt embarrassed and like I was shaming her for being a mom. She said she didn’t think it would be a big deal and that if people were uncomfortable, that was on them. Now she’s barely responding to my messages and told our mom that I "humiliated her over nothing."

I don’t think I was out of line for being honest. It wasn’t a baby-friendly event and I gave her a heads-up. I didn’t yell or make a scene — I just told her how it came across. AITA?