Sexiest Supergirl Comic Book Covers
A Dream Girl Becomes Supergirl
There is some confusion about the first appearance of Supergirl. Most collectors gravitate to Action Comics #252 (May 1959), which in fact does feature the 1st app and origin of Supergirl (Kara Zor-El).
The character’s first true appearance, one might argue, was nine months prior, in her cousin’s comic, Superman #123 (August 1958). This comic features the first appearance of the character as a prototype in a dream sequence. The character’s name? Is she Superman’s cousin in the dream sequence? What is different about her?
Sources: GoCollect (“The True First Appearance of Supergirl“)