Hilary Swank was 16 in Buffy the Vampire Slayer when she played the character 'Kimberly Hannah'.
That was over 32 years ago in 1992.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 49, and has starred in 50 movies in total, 47 of those since Buffy the Vampire Slayer was released.
In Buffy the Vampire Slayer, I think Hilary Swank looks: