Captain Marvel (DC Comics) Comics" #21 (1941) introduced the Lieutenant Marvels: three other boys named "Billy Batson" who could also become adult superheroes. Captain Marvel, Jr., the alter-ego of disabled newsboy Freddy Freeman, debuted in "Whiz Comics" #25 (1941). Mary Marvel, alter-ego of Billy's twin sister Mary Batson, first appeared in "Captain Marvel Adventures" #18 (1942). In contrast to Captain Marvel and the Lieutenants, both Mary Marvel and Captain Marvel, Jr. remained kids in superhero form, and were given their own eponymous books in addition to appearing as the lead features in "Master Comics" and "Wow Comics", respectively. Captain Marvel, Captain Marvel Jr., and
Captain Marvel Jr. a Marvel-esque lightning bolt insignia) also show inspiration from Captain Marvel Jr. Elvis's childhood collection of "Captain Marvel Jr." comic books still sits in the attic at his Graceland estate in Memphis, Tennessee, with a copy of "Captain Marvel Jr." #51 (1947) placed on the desk in the recreation of his childhood room at Memphis' Lauderdale Courts housing complex. In reference to Elvis's admiration for the character, Captain Marvel Jr. has often been shown as either a fan of Elvis or having been inspired by Elvis. In "Teen Titans" (vol. 3) #23, Captain Marvel Jr. is revealed to be a