All people in the U.S. have rights. Even children. If you don't think so, try not getting your child health care when he's seriously ill. The govt will step in (as in this case), and make sure he gets it.. Try beating up your child. You'll find out fast that the child has rights as to his own body. A child has the right to an education in this country. No parent has the right to prevent a child from receiving an education. A child has the right to support from his parents. Try not feeding and providing some sort of shelter for your child. Try not paying child support. Children also have freedom of speech rights. Not sure about freedom of worship.
Children do have rights. Maybe not the right to refuse care that would string his death out longer. Not sure. But if I understand, the care being forced won't save the kid's life. The girl is terminally ill. It will merely extend the inevitable for a while. I think I read it'd extend it for about 6 months, but I'm not sure.