I think the tui seats are a teeny bit wider than the virgin economy seats but they are still narrow. I hope they haven't booked the seats at the front of the cabin as the arm rests dont go up as the screens and tray tables are in them. Also Barney being over 2 when they go will have to sit with his seat belt on for take off, landing and any periods of time the seat belt signs are on. Do they have some sort of extra restraints for little ones?