Ah yeah, called it. Ugly is in reference to her ugly personality.
No matter her reasoning, throwing a vase at your sister because she was playing with your doll is understandably a horrible deed that needs to be punished.
It seems like the original character had anger management issues. It's hard for her father to even begin considering her side of the story when the argument escalates to violence so often.
Sure they should've worked with her more, but she's also never apologised??