Professor Martin Stein and Professor Martin Styne were each two scientists who spawned the twin energy emitters known as Firestorm and the Ray. Although this two heroes were not counterparts of each other, they each had notable careers on their respective worlds of Earths One and Two. For the Ray, his counterpart on Earth-One was the New Genesis occupant known as Lightray, each possessing the ability to transform into forms of energy, comparable to Stein's alter ego, Firestorm.
Firestorm was two heroes merged into one. Stein's partner, in the driver seat of the Firestorm persona, was athlete Ronnie Raymond. They had encountered one another during a failed protest at a nuclear power plant during a meltdown, when an atomic blast melded these men into a superhuman.
As for Professor Styne, it was while testing his experimental "Strato-Balloon" that reporter Happy Terrill was exposed to a strange electrical storm surge which mutated him into the Ray. Later, the Ray would join us members of the All-Star Squadron in migrating to Earth-X where there were no heroes, leaving his native Earth-Two behind. Another of his fellow Freedom Fighters formerly of Earth-Two was the counterpart to Ronnie Raymond....
Another firebrand jock, himself tutored by an older wiser assistant (ex-boxer Slugger Dunn) was another double "R" like Ronnie, named Rodney Reilly, aka...
And the neat symmetry doesn't stop there. For both atomic aces had redheads that acted as both love interests and, due to exposure to intense radiation, fellow heroes:
First is Lorraine Reilly, daughter of a New York senator, who becomes the flying flaming female known as Firehawk:
And a steel mogul's daughter, Danette Reilly, sister of Rod Reilly, now known as Firebrand (the second):
A real nuclear family, this one is!