Needless tears and whining, Uncle Cam doesn't play that shit.
I explain that I don't believe their tears and tell them to use all of the great words they know--like a big boy. After that, I just ignore them until they decide to speak.
It works!

One of them is a great negotiator and understands the power of manipulation, so he cries only if he thinks his mother is around and he wants her to hold his hand.