I had another idea.

What if the peeps were not only able to keep tabs on their other family members (such as their father's brother or their mother's father), but they could have family events? Such as Christmas or a birthday?

For example, you have the Christmas tree. You drag a peep onto the tree, and a pop-up comes and states that it is getting close to Christmas. You have the options to either invite family or ignore. When you invite family, then the family members that are still alive come over as guests. They would basically chat with your peeps, eat, watch tv, and celebrate around the tree. Then they would leave. There would be a cool down afterwards, for a certain amount of time when you put the peep on the tree it would say "Its not Christmas time yet!"

For birthday parties, when you drag a peep to the cake, it would show a pop-up that would ask who's birthday it is. It would have all of the current family members. Then, the same thing, where the guests would come over and hang out for a bit then leave. There would be a separate cool down for each person, and each party wouldn't actually affect their age. Or maybe it will. I don't know.