Incidentally, some people who were present in the terminal before the family boarded say the girl was acting wild and out of control in the waiting area too. And the child's behavior on GMA also makes it hard to believe she's "usually well behaved", as the parents claim.
The airline ought to start a class-action counter-suit with a bunch of the passengers on the plane for their inconvenience.
The girl was hitting her mother. Why should 60 other people (or however many were on the plane) miss their connecting flights or be late to meetings and so on because one uncontrollable kid. If the flight took off without the kid belted in and something happened to the kid, you know they would've sued. Here's a clear case where the airline was damned either way.
These young parents nowadays think their kids are little gods.