Okay, so I know that when you leave the game for a while, when you open it again, it will automatically decide what should have happened while you were gone. Also, sometimes the babies that are born are grouped so that there are two or more children with the same mother and different fathers that are the same age. I've seen that a few times, but never like this:
Surely you must concede that this is a bit of an oddity.
(When I first saw these kids, I though they were twins.)