I know the music and fruit is true I tested it with one of my families. The games mechanics is very simply when determining if the next gender is going to be a boy or girl it counts how many girls and guys are in the game and uses that as a reference point for what the higher percentage is. If there is more girls in the population the higher chance is a boy, if there is more boys in the population the higher chance is a girl. If the game is near the cull stage, the game will produce boys because boys can't have kids, except with aliens.