Alyson Stoner was 9 in Cheaper by the Dozen when she played the character 'Sarah Baker'.
That was over 19 years ago in 2003.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 29, and has starred in 35 movies in total, 34 of those since Cheaper by the Dozen was released.
In Cheaper by the Dozen, I think Alyson Stoner looks: