Two Harvard-affiliated researchers, David Ludwig and Lindsey Murtagh, have a piece in the Journal of the American Medical Association that says the government should take children away from their parents if the children weigh too much. According to their Journal article, "Even relatively mild parenting deficiencies, such as having excessive junk food in the home or failing to model a physically active lifestyle, may contribute to a child's weight problem."
USA Today has more: "'Despite the discomfort posed by state intervention, it may sometimes be necessary to protect a child,' Murtagh said."