AITA for not letting my sister bring her kid to my wedding?

My (23F) fiance (24M) and I are getting married on the beach. It's a small intimate wedding with about 100 people. We were thinking about having a kid free wedding but as the guest list got bigger and there are a lot of family, we decided to allow kids but as long as they are supervised by their parents at all times. We've been planning this for over a year now. We've always been clear about this. <br><br>This is where the problem starts. My sister (28F) has 2 boys, one is 6 and the other is 3. When I told her she was welcomed to bring them with as long as they are supervised, she said no she'll find a baby sitter. I was confused but assumed she wanted a night out. Well not long as she texted asking if bring her kids would be okay. I reminded her of what I said before and she got upset.<br><br><br>It went back and forth for a while until I just said "look either bring them or don't it doesn't matter". She told me as long as I didn't expect her to bring them it was fine. I assumed she was just being weird.<br><br><br>Well now she's telling me she's bringing the kids. I reminded her of the rules and she told me she was going to drop them off at the hotel across the street and I can pay for it. I said hell no. She called me an AH for not letting her bring the kids. Now my parents are pissed at me as well for not letting her bring her kids.<br><br><br>I feel like I'm the victim here not the AH.