The issue of whether it's a good idea to take fat kids into protective custody (i.e. foster care) seems to be popping up again. Here's a recent LA Times story.
http://www.latimes.com/news/health/la-heb-childhood-obesity-neglect-20100715,0,545105,print.story
http://www.latimes.com/news/health/la-heb-childhood-obesity-neglect-20100715,0,545105,print.story