Does southwest enforce the issue of the fare buyer being over 18? we bought 3 tickets and got 3 free and want to use with all of our kids but, the last set will be 2 children. It seems silly that the price would be cheaper if one of them was over 18, usually children fares are cheaper. we went ahead and bought them and thought that if they make us pay the difference at the time, fine. Just wondering how strict they are? we are hoping that by not checking any luggage that we can just get through sercurity and board.