In Superman #123 (June 1958), the creators of Superman test the waters with a prototype Supergirl. Jimmy gains a magic totem that grants three wishes once a century and his first wish is that Superman have a female companion that matches all his powers. Despite all her efforts, she ends up annoying Superman, and in the end, sacrifices her life via fatal kryptonite exposure. The design of this prototype Supergirl almost completely matches the eventual costume of Kara Zor-El except for the skirt being red and shorter.