I would have to respectfully disagree with Dan. The essence of the argument is that a parent should have the right to refuse medical attention for their child even if doing so is deemed "life threatening" by the government. Should a minor be forced to have an abortion if giving birth is deemed "life threatening" by the government, even if it is against the parents' wishes? Should an obese child be forced to go on a diet if the child's weight is deemed "life threatening" by the government, even if it is against the parents' wishes?
You may argue for child abuse, but if nothing else in the family's history points to purposeful cruelty to the child, than there is no case. You may strongly disagree with the family's wishes, but the power of persuasion is the proper tool to use, not the hammer (and sickle) of government.