& Anya.
Hybrids get less consistent traits, but their children inherit their vampire traits (unless they have kids with another hybrid, in which case it's a 50/50, or a vampire, in which case it's another lottery). Their sleep cycle is based on the sun's position in the sky.
Examples:
Selena Morgenstern (half-vampire mother, vampire father): non-venomous, capable of living off human food or blood, sleeps 5 1/2 hours every 24, doesn't mate.
Angela Morgenstern (half-vampire mother, vampire father): venomous, requires at least some blood but can also eat human food, sleeps 4 hours every 24, does mate.