Grey DeLisle was 36 in Phineas and Ferb: The Movie: Across the 2nd Dimension when she played the character 'Additional Voices'.
That was over 13 years ago in 2011.
Today she is 50, and has starred in 199 movies in total, 108 of those since Phineas and Ferb: The Movie: Across the 2nd Dimension was released.
In Phineas and Ferb: The Movie: Across the 2nd Dimension, I think Grey DeLisle looks: