About 12 years ago my brother in-law and his wife got divorced and gave up custody of there 2 kids. The younger one lived with a great uncle and his wife. They recently got divorced and she now lives with the woman. She is no blood relation. The little girl has rotten teeth and her head has sores all over it. She is about to move out of state with her. I would like to try and get custody of her. Is this at all possible?

Hi,
You need a lawyer; one suggested by someone locally, who is experienced with child custody cases. He/she can give you an opinion, and if there is a chance, get the ball rolling. There will have to be an investigation into the child's life, possibly by Social Services, or Child Services in your local area.
I would call a lawyer now, and not wait any longer.
I do wish you the best, and good luck.