There is a law in Florida (named after a child but I can't remember the name off hand as I'm brain dead), whereby if a mother does not want their child, they can drop them off anonymously at a hospital or fire station. I don't think there is an age limit either, meaning it doesn't have to be an infant - can be older. If (and that's a big if) Caylee was kidnapped, this would be "an out" that any potential kidnapper or "holder" of Caylee would have to bring Caylee back to safety, anonymously.
Seems that the GM and GP could at least mention this fact every once in a while as they are doing all of these tv interviews IMO.