It happened to me once. I had two women designated as parents and when I turned the game on one morning, I had 20 women caring for children. I had been doing well keeping my tribe all blonde, not letting the occasional dark haired villager have babies, until that point. All the children had dark hair and their father was "?". I figured that the gong had granted life during the night, although I had not rung it. What a mess when they all turned 14 at the same time!