The above card is of Carrie De Mar, Joseph Hart’s wife and fellow performer circa 1915. Blanche and Harry Mars worked for Joseph Hart through the Rain Dears Co. Here’s a little information on Joseph Hart thanks to Wikipedia:
Joseph Hart (June 8, 1861 – October 3, 1921) was an American vaudevillian entertainer, manager, producer and songwriter.
While still in his teens Hart began touring with I. W. Baird’s Minstrel Show as an end man, the musician stationed at the end of a line of performers. Soon Hart became a crowd favorite for his banjo playing, singing and comedy routines that he often wrote himself.
Later he joined other minstrel troupes such as Simmons and Slocomb and Tony Pastors Minstrels before entering vaudeville to play Ko-Ko in W. S. Gilbert and Arthur Sullivan‘s Mikado and as a performer in Princess Ida.
In 1888 he joined forces with Frederick Hallen as Hallen and Hart and toured for six years in Later On, a musical comedy written by himself and H. Grattan Donnelly. This success was followed by a two year run of The Idea, written with Herbert Hall Winslow.
Hart next struck out on his own touring with his play The Gay Old Boy (1894–95), A Tarrytown Widow (1897–98), by C. T. Dazey, Foxy Grandpa (an adaptation from the Carl E. Schultze comic strip, 1901–05) and Girls Will Be Girls (1903–04), the latter two written in collaboration with Melville Baker. Hart and his wife, Carrie DeMar, later reprised their Foxy Grandpa roles in two short films, The Boys Think They Have One on Foxy Grandpa and Foxy Grandpa and Polly in a Little Hilarity.
Hart’s later years were primarily spent as a writer and producer of vaudeville shows.
Joseph Hart and Carrie De Mar were easily found when I was doing my research online. And to my surprise, I found the 2 silent films mentioned by Wikipedia above, provided by the Library of Congress:
If only it were this easy to search for the other names in my card collection!