As for the timescales, that is an aspect of a thing I discussed here. That years in stonehearth take so long IRL that IRL processes that take years only take days in stonehearth, because it would otherwise be unplayable. I believe that making years shorter is a good step to an answer there. I would expect a hearthlings lifetime to be longer than a year, festivals and such don’t really make sense to me when you only get to experience one instance over the course of your life time, is it even a tradition then?
I like the idea of children fleeing during combat. Maybe to prevent all adults being murdered and leaving the children to die, maybe the adults go on parent-duty. A bit like a designated (adult) survivor. When it looks like all adults are going to die, the adult on duty that day will seek shelter with the kids. If that doesn’t work (adults just have less hiding options) and the hearthling is attacked, he/she will fall unconscious prematurely. What the enemy doesn’t know, but the player does (red hearth above the ‘unconscious’ hearthling) is that this hearthling is faking it. The adult wakes up when the danger is over and wanders off with the children.
Maybe in the citizens menu the player can then determine who can go on parent-duty, and it will cycle every day.