Ernestine “Tiny” Davis was the star trumpet player for the International Sweethearts of Rhythm. Born Ernestine Carroll, in Memphis, TN, Tiny began playing trumpet at age 13. Eventually, she moved to Kansas City and played with the Harlem Play-Girls from 1935-36 until taking a brief hiatus to give birth to her daughter. In the late 30’s, early 40’s, she was separated from her husband and children and answered an ad to join the Sweethearts. She soon became an integral part of the group with her boisterous presence and impressive trumpet chops. Vicki Lynn Eaklor writes,
Davis was “described as the ‘heart of the band.’” Eaklor goes on to write “Davis…was known widely in jazz circles as ’the female Louis Armstrong.’ Ironically, Armstrong was among the band’s and Tiny’s fans (Count Basie and Ella Fitzgerald were others) and reportedly offered Davis up to ten times her $150/week salary to join his band.” But she chose not to go because she “loved them gals too much.”  Here’s an example of her animated stage persona and powerful trumpet playing:
She did eventually leave the Sweethearts to form her own band, soon after WWII ended (the Sweethearts disbanded in 1949), which she called Tiny Davis and Her Hell-Divers. The Hell-Divers were Decca Records’ first all-female recording artists.  I’d love to hear the sides they recorded but I haven’t been able to find them.
Around the time she formed the Hell-Divers, Tiny met her life partner, drummer Ruby Lucas. They ran a club in Chicago called “Tiny and Ruby’s Gay Spot” through the 1950’s. They were together 40-some years, until Tiny’s death in 1994. 
Tiny continued to play music with her group through the 70’s, including her daughter Dorothy on piano and bass (she also played trumpet.). There is some great footage of her horsing around as an older lady playing trumpet with her grandson in the playlist below.
Tiny Davis was an absolute powerhouse and I wish there were more recordings of her!
Here is a playlist of all the relevant videos I could find, and here is that International Sweethearts of Rhythm playlist again.
 Vicki Lynn Eaklor. Queer America: A GLBT History of the 20th Century. London: Greenwood Press, 2008.
 Linda Dahl, Stormy Weather: The Music and Lives of a Century of Jazzwomen. (New York: Pantheon Books, 1984).
 Unknown Author. “The History Post Blog.” http://www.thehistorypostblog.co.uk/tag/ernestine-tiny-davis/