Did you have assigned seats or not? You made it seem like you did and they switched you. Every family flight I’ve booked, I’ve made sure our seats were together during the purchase. If you didn’t get assigned seats or didn’t pay extra to choose seats then I don’t see what the airline did wrong. I’ve got 3 boys and when I got tickets to a Panthers game, I had limited options because I was looking for 5 seats, but I made sure we had 5 together. On the flights, I made sure I found 2 and 3 together. It wasn’t difficult.