Do you know the title of this movie?

A friend told me about it, said she used to really like to watch it but doesn't remember the title. About a young girl who has mentally handicapped parents, she is "normal." She goes to Baton Rouge? For some reason? Visit maybe? She has her hair cut really short and there is a (I think she said black) lady that says to her at some point that at least she got it cut on a full moon (that way it'll grow back faster.) I know it's not a lot to go on but any suggestions will be great!