Well I decided that for this pregnancy, I'd have my baby at home because I already had a bassinet. So the child is born and it turns out that it's twins! Hooray! However, there was a problem with this. After the dialogs and animations for the birth, I only had one bassinet and one child. Both children were not in one bassinet. So I decided to buy an extra one to see if that rectified the situation. No. I then restarted my save with two bassinets to see if the other child would magically appear. That didn't work either. I'm not really sure what to do at this point. For now, I'm just going to make a new save at this point and continue playing to see if there's any change.
Screenshot here.As you can see I have both babies on the sim icon things, but only one in a bassinet. Those are the only two bassinets on the lot.
EDIT: I randomly found the other twin in a bassinet in the kitchen
after making this post.