Taylor Momsen was 6 in How the Grinch Stole Christmas when she played the character 'Cindy Lou Who'.
That was over 23 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 30, and has starred in 13 movies in total, 11 of those since How the Grinch Stole Christmas was released.
In How the Grinch Stole Christmas, I think Taylor Momsen looks: