Marriage on the move

In my Julii campaign, I have a lot of governors sitting about in their cities for a long time.
The campaign is practically over, but I am delaying victory while trying some stuff, so the number of provinces has been stable ~48 for a long time - meaning I do not get many new family members. (The generation that came with the last great expansion has not begun to die yet.)

Now I notice that when these governors in their late 30's or early 40's leave their city en route to another post (i.e. end their turn in the field) they get married that turn.

Coincidence?

Has anyone observed somthing similar?

I believe I have read somewhere that the chance of having children depends on staying in a city. Apparently the same does not hold true for getting married?

Never really paid close attention to this... Good finding though.