Since they have to have specific traits for the Not So Berry challenge and I don't want a bunch of kids with the same traits - in my play - each gen only has one child (just easier to focus only on one child too!) - other than Orange which has to have twins - and then it must have started a thing because the next gen Pink had twins too! For the twins I just pick one when they age to a child and have to have traits assigned - the other twin usually gets opposite traits. Kind of funny in the current gen - Peach has a twin - Peach's traits are Foodie, Lazy, Goofball so I made her twin's Glutton, Active, Sad - the glutton and active together are kind of funny - she pigs out all the time if left on her own and then goes and exercises like crazy!