Need help for my 3 year old daughters dry frizzy hair?????  

My 3 year old grandaughter has very dry, frizzy hair. When it is wet and still damp it is beautiful, but when it dries it is a dry, brittle, frizzy mess. It sticks like a bad fro. I desperatly need help with this childs hair. She is a beautiful child but I cannot do a thing with her hair. I have tried many things like shampooing once a week, leaving conditioner in her hair. Not combing, not brushing using my fingers to comb. I am open for any and all ideas. It is to the point now that it is difficult to just brush her hair it is so dry and brittle and frizzy. I just don't know what to do.