I have custody of my little sister. She's so unhappy and I don't know what to do.

I have custody of my little (half) sister. When she moved in with me she changed schools, going from a large public school to a smaller private one (which has much better academics but a cruel social scene). She is extremely unhappy there.It seems like all of the girls have know each other since kindergarten and she's the odd one out. She's tried to be social and reach out but you know how cruel 7th grade girls can be. Today, I took her to the movies and we ran into a few people from her class with one of their moms. The Mom looked really awkward and I couldn't tell why. My sister was excited at first to see them but they kind of brushed her off. Then we passed by a huge group of girls and I realized that one of her classmates was having a birthday party. My sisters face fell and she asked me if we could just go home. On the way home she told me she didn't want to talk about it. She's been in her room since we got home and she doesn't want to talk to me at all.There have been other issues with the girls at the school but this really takes the cake. I've promised her that at the end of the semester she can switch back to her old public school.She's already in therapy and I've emailed her therapist (I don't expect her to tell me anything but just to update her on the situation).I guess I have a two part question:1) How to help my little sister now and comfort her about the current situation and 2) Should I switch her back in the middle of the semester? Is this even possible?Any advice would be appreciated. via /r/Parenting http://ift.tt/2fjIfdf