Vampire babies?

Vamps aren't affected by the sun when indoors, such as a school. When they are out in the sun the effect isn't that bad either way...and they only get it sometimes. I've had my vamp out in the sun quite a few times and she never got the moodlet.

I currently have a vampire toddler and vampire child in my game (in another family) so I know they don't have to wait to be teens. I'm guessing they're either born that way or not.