He said she was cuter then our baby

My partner and I have children from other relationships and just recently had a daughter together. He has four kids, two older and not living in our house and two who are still young, 6 girl and 7 boy then I have a daughter 4 from a previous relationship and we now have our 1 month old girl. His youngest daughter has major behavioural problems and is a complete daddy’s girl as he’s raised his kids alone there’s never been a mother figure.. she’s a sweet girl, I love her so much and it sits heavy on me that she is struggling right now… but she’s hard. She’s got en entitlement issue. Her way or no way, everything is her and nobody else’s and beats on other kids especially her siblings, she can be so fucking mean. The schools had issues with her behaviours and asked to drop from full time to part time school.. we’re trying to work on it with her at home but the biggest problem is that she acts entitled. She can say, do and take what she wants and nobody else matters and when she’s stood up to by her siblings, classmates and even adults she fights. So at home we’ve been trying to work on reminding her she can’t do those things and she is equal to the people around her especially her siblings. She’s had a rough go with the new baby, any attention given to the baby makes her act out, it’s hard. I find my partner is distancing himself from our daughter and even his son and my other daughter because of her and will specifically focus attention only on her and put her on some pedestal above everyone else. It’s seriously come to the point where if he acknowledges me she gets right in the middle and then he’s bowing to her and shoving me to the side. I get it, roles reversed I couldn’t deny my daughter love and affection but at the same time I’d never allow her to act the way she does and id never make her siblings feel like they were less important and most importantly I’d never have her feel she’s above anyone else in our home.

Anyways, we were sitting there and they were looking at our baby and she said she’s kinda cute he dead ass turned to her and said she is cute but not as cute as you and I wanted to literally throat punch him… I’d NEVER say that to my daughter. It wouldn’t even cross my mind. Especially considering we’re already struggling with this behaviour, like this shit doesn’t help. Now she’s walking around Im cuter then the baby Im cuter then my siblings and they’re getting offended and it hurts their feelings… like I can see their faces sometimes when they watch her and my partner. I know they don’t get it or understand why. Am I wrong for being offended?