So I don't know if anyone has done this work already, but if not, buckle in!
At the fortress of Flewclutch, SCIENCE! is happening!
After a bit of twiddling, I managed to net a breeding pair … of visiting bards! (Well… I got a pair of bards and, how should I say… persuaded them to marry? No matter. They are here and breeding. That's what's important.)
The first insight is that children borne of this union, even before their citizenship petition (but after their residency petition), are immediately granted citizenship at the fort. What exactly that means for labor will have to wait another … ugh. 12 years. Hey ho.
Still: Lesson one:
Married long-term residents get pregnant if married, and give birth. They carry around their babies like everyone else, nothing silly going on there.
Lesson two:
Babies are given immediate citizenship, it seems.
Lesson three:
Lesson three will have to wait about 9 months, for when the babies become children. Provisional assumption: Kids will be kids, participate in play, etc. Time will tell!
Lesson three update:
Provisional assumption vindicated: Children appear to play and be merry as usual. Great success!
Lesson four:
Children of migrants appear to inherit the cultural values of their parents. Good to know!
Lesson five:
Children of migrants, upon growing up, become, near as I can tell, full-fledged members of the fort in every way, assignable to professions, positions, jobs and squads.
Lesson six:
Children of migrants will take up the gods of the fortress they are born into, at least if they don't inherit any from their parents. More research needed to determine the situation where they do inherit.