How old is Ava? Is she ageless?

I was thinking about how she is a founding member of the Roots and attended university with Crystal? I think they attended uni around late 90s. So it makes them like early-mid 40s BUT the roots were from late 80s? Unless she was 6 during that, she is in her 50s. THERE IS NO WAY AVA IS IN HER 50s. Maybe she is a vampire idk.