@Marceline_Reyes - I hope you put pastries in that summoning circle to get me here…hehehehe! ;D
I actually have one canon birthday of F’s, not long after they joined UB and learned about birthdays, lol. They went to one of those go-karting tracks and well…combine F’s very excited hyper birthday mood with A’s overcompetitiveness and let’s just The Agency were called in for some cover-up duties after that day.
And that’s why there was a long-standing memo about how birthdays are also not ‘let’s-show-the-human-world-we’re-supernatural-day’ 
As for F’s age…trying to decide it that’s spoilery or not…I guess it wouldn’t be because F’s age is not linked to a particular time in our world.
F is around late 60’s/70 years old, though it’s not a for sure thing. That’s an estimation. Very young for a vampire, especially a natural vampire.
Hope everyone has a great day and revels in F’s birthday joy 
(and you’re gonna do amazingly well on your test @rose-court !!)