 Part of this decision was based on the fact that in the 1920s, her father became ill, so Gilbert was needed to help support her parents.At this time, she self-taught herself the alto saxophone, as she was told it was not suitable for young women, and joined the Musicians Union in Sioux City.Gilbert organized her first band in Sioux City, a group that was composed of Gilbert on the saxophone and clarinet, Marjorie Kelley on piano, Dorothy Kelley on banjo and accordion, Orval Knechtges on drums, Ruth Dubnoff on violin, and two other men on trumpet and bass.