Born in Salt Lake City, Utah, Kearns moved with his family to California when he was very young. His mother was Cordelia M. Kearns (née Peterson; 1877–1962), a concert Pianist, from whom Kearns derived his love of music. He and his family were strict Mormons, whose ancestors were Mormon pioneers. His acting career began in 1916 when he joined 'The Rising Generation", a vaudeville troupe of eleven children that toured for 14 months. He briefly tried his hand at wool buying and worked for his father for a year. Kearns traveled the West as a representative of Howell, Jones and Donnell of Boston. His wool-buying career came to an abrupt end when Kearns purchased five boxcars full of black wool from a breed called Karakul for $8,000. The Problem was that black wool could not be dyed and no one knew how to use it in those days. After this fiasco, Kearns gladly gave up the wool Business and pursued a show Business career.