My daughter (7) doesn't like her dad

When my daughter was younger she would always be really happy when her dad would come and get her. Her dad and I have broken up when she was about 2, so she doesn't really remember us being together. She used to hang out with him or go to his home about every 2 weeks. All of a sudden, she just doesn't like him. Apparently, she and her sister (dad's side) got into a fight over some nail polish stuff and started fighting with each other. Her dad then broke them up and she became really upset and told him that she didn't like him and never wanted to go back. We just brushed it off as her being upset with her sister but a few weeks passed and he wants to come and get her again. I told her to pack up her clothes because she was going to her dad's house and she says, "I don't like daddy. I hate him." I told her to watch her mouth and explain to me why she doesn't want to go. She tells me that she just doesn't and that she wishes he was never her dad.I asked him if he yelled at her at all or seemed angry after she and her sister were fighting and he said that he was calm towards both of them but she became upset. He came to the house to try and get her anyway and she just refused to go. She just sat on her floor saying, "I'm not going" and told him that she didn't like him repeatedly. He got on the floor to act like he wanted to play with her, but she told him not to touch her toys. His feelings are really hurt by this and we have a very good co-parenting relationship. I'm not really sure what to do at this point. I don't know why she doesn't like her dad. Even she doesn't know why she doesn't like her dad. via /r/Parenting https://ift.tt/2ML8POx