Betty Boop and Baby Esther: The Untold Story Betty Boop, introduced in 1930, became famous for her flirty “boop‑boop‑a‑doop” voice, closely associated with singer Helen Kane. Kane sued Fleischer Studios, claiming Betty copied her style. The case turned when defense showed footage of Baby Esther, a Black jazz performer, using the same scat singing years earlier. Kane had actually adopted Esther’s act. The court ruled against Kane, and Betty Boop remained iconic. Baby Esther never got her due cred