So I'm not sure if we've all agreed on this or not, but I think it's generally accepted in the Vat7k fandom that Ulla was around 16-20 when she started the trials (collage/high school years). Also, we know that she met Quirin in the Dark Kingdom and then had a kid with him.
She was definitely over the age of consent, which means that she was probably 20-22 when she had Varian, making her around 20 years older than him (38-40 in Vat7k).
Donella was probably a year or two older, making her 21-23 years older than Hugo, around 39-41 (most likely 39 or 40).
So these badasses aren't even old. Hell, they're probably younger than your mother ToT
I personally think that Ulla was/is 38 and Donella's 39.
YIPPEEEEE (i've been thinking about this since Saturday lol; tell me what you think!)
Edit: I just mean this as a 'what if' kind of headcanon. I'm not saying I think it's canon, or that it would've been, but I just think it's cool that there's a possibility. Also, someone pointed out that she has grey hair. Uhmmm Ulla and Momella were at the Eternal Library, so there's a chance it had some sort of aging spell in it (Varian also got possesed by his mother who looks 18, so she might not have aged much either 🥲)
but again; it's just a theory
A FILM THEORY- ok i'll stop now