Going to Disney Paris with 2 DC who will be 5 and 3 (almost 4 though). Struggling to decide about car seats. Older DC is 22kg so I think they can go into the bubble bum booster (it's just for one short taxi ride on arrival and departure). Younger DC is almost 18kg and so I'm not sure what to do about them. I am trying to find out if I can hire a seat but otherwise wondering should I take the bubble bum as a back up? DC is still rear facing here but I can't take their rear facing seat and I'm struggling to find an easy seat to take with us.