Among other things, I too had a young villager who would not age, ever, and had a farmer with "running" under his likes who suddenly refused "all" work "all" the time because he was caught within a continuous "waiting for someone" loop.
I know that leaders of the village get pestered by the others frequently with social events, such as chatting, praising, or complaining. Perhaps your farmer was in a leadership position? It's hard to tell if you don't have the GC, but typically all the children of the village are "on the left" and the oldest members are "on the right" of the leader (look at the details screen, see the arrows at the bottom, and you'll understand what I'm talking about.)