Blake Lively was 16 in The Sisterhood of the Traveling Pants when she played the character 'Bridget Vreeland'.
That was over 19 years ago in 2005.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 36, and has starred in 27 movies in total, 21 of those since The Sisterhood of the Traveling Pants was released.
In The Sisterhood of the Traveling Pants, I think Blake Lively looks: