Well I see now why my random generated characters's gfx culture would suddenly change lol...
If I delete the on_birth trigger of blg.2, would it prevent ethnicity change? Or that the gfx culture of the children wouldn't match their parents'?
Edit: It seems that blg.1 controls randomisation. Do you have some suggestions of quick fixes for blg.2 so that sicilian graphic culture is not overly spawned? Say I don't want graphical culture randomness in courtier generations but I do like to have the mixed-race events for the children?
Edit2: Now I see why the Sicilian graphic culture keeps spawning, if one of the parents are byzantine/levantine, and father is not of byzantine group, mother is not of steppe/Chinese group, the children will always be Sicilian. Seems like an oversight in the condition of #Byzantine-European part. in blg.2 Is there a convenient way to include all western european cultures without enumerating? (It seems the answer is no, judging from your file.)