I've found Carnival also attracts a lot of young couples, but they also attract a lot of families, as does Royal Carribean. In order to avoid a lot of kids don't cruise during the summer, over the holidays, or school vacation weeks (mid-February through the end of April). I will say I have cruised with my kids during a school vacation week and while there were a lot of children on board, I didn't feel as though the ship were over-run with them and overall all the children were well behaved.