Set a household free to do what they want but not be culled

What I mean is it's the household that's marked "played", not the individual sim. So if a sim that was in a played household and therefore protected from one aspect of story progression marries into an unplayed household then that sim won't be counted as "played" any more so will get story progression applied along with the other sims in her new unplayed household. I might have allowed played sims to move out and marry but not have allowed them to age or change jobs, for example.