Originally read for the role of "Bart" when auditioning for The Simpsons (1989), but her voice was too high and sounded like a girl, so she lightened her voice up a little and then auditioned and won the role of "Lisa". Nancy Cartwright had originally read for "Lisa", but was given the role of "Bart" instead.
Is only one of two actresses (the other being Marcia Wallace) on The Simpsons (1989) to
regularly play only one character. Most of the other actors play ten or
more characters, while Julie Kavner plays four characters and Phil Hartman played two characters.
Her father, J.Y. Smith, who died in 2006, was a longtime obituary
writer for The Washington Post.
Her forename is pronounced "Yard-lee".
Of the core 6 The Simpsons performers, Yeardley is the youngest.
Starring in Balancing Act at the Falcon Theatre in
Burbank, California. (April 2007)
She is a lifelong Democrat.
Is exactly 5 years the senior of Shawnee Smith ("The Blob", "Saw"), and exactly 21 years the junior of Kurtwood Smith ("Robocop", "That 70's Show"). None of the Smiths are related, however.