In 30th Century Earth-One, Dirk was a young assistant to Doctor Regulus in the power plant of Dirk's father. Exposed to nuclear energies when Regulus trapped the youth in a chamber out of revenge, the lad gained solar based powers. Adopting the moniker Sun Boy, he quickly joined the Legion of Super-Heroes.
Blaze Barton was the assistant to renowned 30th century scientist Professor Solis on Earth-Two. When sections of that world in one possible future were overheating, a mass migration was determined to me necessary for humanity's survival. To that end, Blaze and Solis' daughter Betty had a series of adventures throughout the solar system to restore order, using blasters and even at one point a freeze ray!
Sun Boy had a long standing enmity with his former employer in Regulus, who equipped himself with gold armor to replication Dirk's heat generating powers. Blaze and Solis, however, had a spot on solid relationship as mentor and student. Similarly, Blaze was faithful to Betty while Dirk wasn't quite so with his own girlfriend Gigi Cusimano. Nevertheless, both young red headed heroes tempered flaming dispositions with a true love of justice and loyalty to those on the right side on the law.