.

Actually a story from a few years ago, before I was on FT, but a good one.

My father decided to fly with my 4 years old son (his grandson) to Disneyland. He called AA and told them the plan and that the kid's last name is different than his last name. Does he need any doc from parents?
AA answer: If the kid does not cry and screams that he does not want to fly with you, then there is no problem. No docs needed.

This was a domestic flight. I wonder what about international flights.