Pettyjohn was born in
Los Angeles,
California. Prior to her film and television career, she performed alongside a local children's song and dance troupe from the age of seven. Pettyjohn has also played various roles in several television series, such as in
Revolution,
Criminal Minds: Suspect Behavior,
Grimm,
The United States Of Tara,
The Mentalist, and
Pure Genius. She co-starred in the Nickelodeon Original Movie
Rufus 2 which aired in January 2017. In September 2017, Pettyjohn was cast as
Laura Dern's daughter in the movie
Trial by Fire. Additionally, she was added to the cast of the crime thriller film
Destroyer, and appeared in the film
Against All Enemies. In late 2018, Pettyjohn was cast in
Deadwood: The Movie, playing the role of Caroline, a newcomer to the town of Deadwood. In 2019 she was cast in the
Hulu television series
Little Fires Everywhere playing Lexie Richardson, the daughter of
Reese Witherspoon's character. In June 2020, it was announced that Pettyjohn had been cast in the ABC television drama series
Big Sky, playing Grace Sullivan who is kidnapped along with her older sister Danielle (
Natalie Alyn Lind). Pettyjohn is a
Scientologist. ==Filmography==