I've coached both boys and girls teams for several years. One thing I've noticed is that families of boys will make a commitment to be at just about all of the games, vacations will be scheduled after the season or around the schedule. Girls families will just pick up and take off at any point during the season, even at tournament time.
Case in point, at our end of the season U-12 softball tournament, 3 of the teams in our league forfeited their tournament games because they didn't have enough players. Kids were gone on vacation/ camps, etc.