What to do about Shyanne?

I think Frankee is making a huge mistake by sending her daughter to live with her sister. Her sister is of the belief system that she will forget her mother if she doesn't talk to her. She refused to let her have ANY contact the last time she was there and won't even let her know where she lives or the phone number to the house. They are trying to send her to private school and that will make her 6th school this year. She started Kindergarten with her Mother, DFCS sent her to her Gpa's, then her aunt within 2 weeks, her aunt moved, then to us, and now back to aunt. All that since September. She is so delayed in school that it is not even funny. I am not sure if I am hurt and reacting to my feelings of rejection or if it is really in her best interest that she should stay here. I can't figure this out and she does want to go there but she says it is b/c she misses the horses and dog. She is the only child there but she was also told her Mother would live very close by. I am confused and very concerned about this child's future. This aunt threw out her pregnant 16 yr old to live with her 26 yr old boyfriend and has only been living with her partner for a few months herself. I think her partner is a lovely woman but the aunt has not always been a good parent, she herself had lost custody of her children several years ago to her ex husband and has no contact with her son at all. Her daughter only lived with her briefly until she became pregnant. I just don't know what to do. I think I could fight but should I? Shyanne, Frankee, and her sisters all say she should stay with family, I agree in most cases but Frankee was so desperate to get her away from her in the first place. I am so sad for this little girl, she is about to lose her Mother.

Edited to add: I discussed this with my wonderful husband and we felt it was completely unfair to Shaynne, we have made the offer to Frankee that she move back in until school is out. She must stay off the computer and focus all her attention on her child. She is taking the weekend to think about it.