What I find quite funny is based on the story, it appears that the husband boarded with the child, leaving the mother behind, until the captain allowed her to sit in the jump seat and opened the door. So, he was prepared to travel without her?
And then once she was allowed on, he put pressure on CE passengers (doing what he reportedly did is akin to emotional blackmail, basically) to allow his wife to sit there. I find that rather strange. If he considered it important that the his wife (mother) travelled with the child, it doesn't really matter whether she's seated in the jump seat or CE?
While I am fairly likely oblige and let her sit in the E seat next to me as long as the passenger in F seat is happy to do so, I would be pretty miffed with the crew for allowing this man to put pressure on people like he is reported to have done to be honest.
In addition, the captain had to open the door to allow her on, incurring a delay and inconveniencing other passengers, because of the man's behaviour, basically. He could have offloaded himself and the child with his wife if travelling together was important, instead of causing a delay and inconveniencing other 150 or so passengers. He could have at least made a decision as to what to do much earlier than after the aircraft door was closed.
The family of three from London were obliged to make two separate bookings because of a strange glitch in the airline's system.
I do not like the way it is presented. It sounds almost as if they made two separate bookings by duress. They didn't have to, of course - they could have made a single booking at a higher cost.
Obviously, it's bad that anyone has been denied boarding, but really, there were many less selfish way of handling the whole thing in my opinion.