Hah oh my setting the mood. 9 months real-time waiting is a bit too much haha! When they manage to have a baby one person will be holding it in their arms, seems like they didn't get it right when they tried. You have 3 villagers but you have the capacity for 5, meaning you have room to make 2 more.
0.5x speed cuts the time which passes in half, so if you leave the game for an hour, it's like 30min has passed on the island. I guess that's effectively the same as them only doing half as much work? And nah, they don't sleep :P