You're correct, the kids will move out before 19y. They go away to college and from what I've seen you may get occasional e-mails from the child but you will not see them unless they take over the house.
When a child is selected to take over the house all remaining sibs (ie: under 19) and remaining parent disappear. I don't know where they go! Nursing homes, foster homes? And you don't see or hear from them. The child taking over moves in as a new adoptee/homeowner (with amenities, upgrades, food, finances remaining). The only child you see marry is the one who takes over the house. And I haven't seen any graduation celebration yet.
Hope that covers it!
