Not since the "we are still looking/who we thought it was, it was not" update. Someone could do this to a child, and there is no way of identifying the child... both stun me.
If you are capable of doing this (or not reporting your child is missing if you weren't the murderer,) you aren't the type who gets the child fingerprints when the Police offer it.
He may not be from the US? Seems a possibility at this point.