From Wikipedia

Rhea Mitchell (December 10, 1890 – September 16, 1957) was an American film actress who began her career during the silent film era. She earned the name of "the little stunt girl" because of her willingness to attempt thrilling scenes in motion pictures.

Mitchell began her career in 1909 playing in the Baker Theatre Stock Company in her hometown of Portland, Oregon. She followed with a season in the Orpheum Circuit and a run at the Alcazar Theatre in San Francisco. Mitchell made her film debut in 1912 with the New York Motion Picture Corporation  and would eventually appear in over 100 films during her career. She appeared a number of times with Western star William S. Hart playing a leading role in those films. In 1916 she played in The Brink with Forrest Winant and Arthur Maude.

After 1917, her roles became smaller and she appeared in a handful of films through the mid-30s and in several bit parts during the early 1950s which often went uncredited.