Should parents of extremely obese children lose custody for not controlling their kids' weight? A provocative commentary in one of the nation's most distinguished medical journals argues yes, and its authors are joining a quiet chorus of advocates who say the government should be allowed to intervene in extreme cases. It has happened a few times in the U.S., and the opinion piece in Wednesday's Journal of the American Medical Association says putting children temporarily in foster care is in some cases more ethical than obesity surgery.