As much as I love Vampires, only one of my save files has Vampires at the moment.
I had a female Vampire that married Caleb, and I edited them a teen daughter. Their teen daughter was blonde like her mom in normal form, and had brown hair in her Vampire form. At night she likes to visit the neighbors and hang out. She and her mom drink plasma from Sims, while Caleb doesn't.
In-game children for my couple included two kids. One child was a daughter with brown hair. Caleb is teaching her about drinking Plasma fruit instead of Plasma from another Sim. Their other child is a son, he is blonde, and so far I haven't decided what path he will take.
I plan to create a Vampire Sim and a Werewolf Sim that are married with a kid.
Also, I will either let Vlad bite one of my Sims, or create a Vampire to compete with Vlad with how many Sims are turned into Vampires.