Originally Posted by
CaptainMiles
You have been stopped where? There is no CBP check on exit, so it is not on exit. If trying to enter (as you imply, "not allowed entry"), well, you can't possibly be trying to abduct a child out of the country when entering. I am confused.
There most definitely can be CBP checks on exit - I've encountered these many times. A child on a booking with one parent could actually be something that would prompt a CBP gate check. You can also encounter Dept. of Treasury checks and other agencies at the point of departure for international flights leaving the US.