Yea, try to do other things and when you go to Savi there is a chance to meet another character.
And for Pregnancy will be added for sure (Like 110%) but it will be later ^^.
Is there anything specific that triggers it? What's the probability of activating the event?
After you had sex with Savi for the first time and a few days pass go to visit her again and you'll see a scene introducing a new character.
If not try to progress other characters and visit her sometimes.
