I was horrified when Celeste knocked her son down, though it wasn’t clear whether she intended to or was just trying to break up the fight. It did make it look like she, just as much as the boys, picked up Perry’s violent tendency. And it was extremely unfortunate to have Mary Louise right there taking it all in. Celeste telling the boys not to “be like HIM” probably didn’t even register with Mary Louise, though, since she has Perry up on such a pedestal.
The hairstyles are similar, but the effect is different. Celeste’s looks great while Jane’s looks harsh because Jane’s hair is so much darker (and the color really doesn’t flatter her) and her bangs seem heavier and blunt-cut, as well as usually uncombed. In terms of the characters, I’d guess the intent is to show that Celeste has a very expensive hairdresser while Jane probably hacked off her own bangs or went to Supercuts.