Can CPS take your kids away if..?

Can the child protective services take your children away if they're over weight? I know that if your child is malnourished they can take your child away, but what happens when your child is seriously over weight? The woman across the street has a 3 year old boy and I swear he weights as much as a 10 year old. He's about 80 pounds and looks horribly unhealthy. I doubt I'd call the CPS but I was just wondering..