Unbelievable!! I understand that flights are often over-booked. That is part of the passenger's risk of not paying for seat selection. You may not get a seat on that particular flight. But I still don't understand any airline pulling someone off an aircraft, where that person has been issued a boarding pass and assigned a seat and particularly where they are actually seated on the plane. How is it possible to issue a boarding pass and a seat to someone else, for a seat that has already been assigned? It seems way too arbitrary. And in this case it was a minor child, and not one of the staff gave a xxxx!
Is their system broken, or is it about someone with higher "status", or in-transit airline staff, being deemed more "important"? Once your seat has been formally assigned it should not be possible to remove someone, unless they are misbehaving. The regulations need to change to severely fine airlines for this type of practice or "error". And I am not talking about just a refund and a few hundred dollars of "compensation". It should be an automatic fine of several thousand dollars. It needs to really hurt the airlines to make them change their ways. It seems to happen way too often these days!