I just got 5 of my ladies off nursing duty and now have about a dozen kids running around...I *planned* to take a break, and I unchecked breeding for everyone. So I'm watching my village and sending straying sims back to their tasks, when I hear a kissing sound, and up pops a message congratulating me on reaching 25 villagers! One of my Master scientists just up and decided she had to have another kid I guess... I didn't think they would do that if they weren't set to be a breeder!!

A villager will perform any activity that they have the skills to do, although they will exhibit a preference for the skill that you have checked. They behave more like people than robots in that regard. Just because you have told them that their job is being a scientist doesn't mean that they won't occasionally do the other things that they know how to do!

..that's how I found out a 65 year old can still have a child! She was supposed to be taking it easy on the research table, but must have got that twinkle in her eye....