Jennifer Jason Leigh was 13 in The Spy Who Never Was when she played the character 'Girl Playing with Ball (uncredited)'.
That was over 48 years ago in 1976.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 62, and has starred in 92 movies in total, 90 of those since The Spy Who Never Was was released.
In The Spy Who Never Was, I think Jennifer Jason Leigh looks: