as far as I know the number of family members is hard-coded, apart from the section of the campaign script that adds family members if there are less than 4 heirs.
with 2TPY instead of 1 it's possible that FMs would have twice as many turns in which to have children, which MIGHT increase the number they produce.
as a rule keep FMs at home if you want children (?)
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OK I'm dipping my toes into modding SS6.3.
I'll do this one or two files at a time to begin with, so nothing drastic.
The RozMod will have the 2TPY and looking at the EDB I can see we'll need to seriously nerf the population growth to make it reasonable.
Having said that the sett mech also needs attention - as human player I was getting 5% pop growth per turn for edinburgh in T17.
which is way too much.
for now an amended EDB which removes pop growth bonuses for the ai, shifts trade bonuses away from walls to buildings, rationalises the various levels etc.
treat as test module for early era - you'll need to restart campaign.
(I've added the sett mech from the old RozMod to see if that slows down growth)
extract into the SS6.3 folder and let me know how you get on.
changes
Attachment 102151