I know. Not very PC. But in the time this game was set in, if you could walk and talk you helped out where ever you could.
I'm aware you try not to take too much from the other game (Banished), but I don't think anyone would blame you for implementing this concept into this one.
You could also make it a bit different. You could make it more realistic by making them join their parents. Maybe not so much building or producing, but rather gathering and hauling.
Making sure the workplace is stocked up, and while mommy or daddy is doing the "difficult part", they go fetch what ever is needed at home.