Sarah Gadon was 12 in The Other Me when she played the character 'Heather'.
That was over 24 years ago in 2000.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 37, and has starred in 47 movies in total, 44 of those since The Other Me was released.
In The Other Me, I think Sarah Gadon looks: