Melissa O'Neil was 29 in A Simple Favor when she played the character 'Beth'.
That was over 6 years ago in 2018.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 35, and has starred in 1 movies in total, 0 of those since A Simple Favor was released.
In A Simple Favor, I think Melissa O'Neil looks: