WARNING: The following contains spoilers for Action Comics #1028, by Brian Michael Bendis, John Romita Jr., Klaus Janson, Brad Anderson and Dave Sharpe, on sale now.
One of the most overdue returns during the DC Rebirth era was Conner Kent, the teenage Superboy cloned from the genetic material of Superman and Lex Luthor. Rediscovered by Young Justice during their recent sojourn in Gemworld, the superhero returned to the DC Universe for the first time since 2011's crossover event Flashpoint to find the world and Superman Family had changed considerably in the interim.
And as Superboy continues to acclimate to the new world and complete his reunion with the Superman Family in Action Comics #1028, he gains a much different standing with Clark Kent, who calls Conner a brother.
In the pre-Flashpoint DCU, Conner regarded himself more as Superman and Luthor's son, given the obvious age gap between them and his origins as a clone developed from their DNA in secret by S.T.A.R. Labs. Luthor used his twisted connection to Kon-El to temporarily take control of Superboy and turn him against his teammates on the Teen Titans, which haunted Conner with the thought that he inherited Luth,or's darker traits from his genetic material. While Conner was killed during Infinite Crisis, he was resurrected by the Legion of Super-Heroes during the crossover event Final Crisis, he was still troubled that he was potentially following in his "father" Lex Luthor's villainous footsteps.
When Young Justice discovered Superboy exiled inside of Gemworld, he had grown visibly older by a couple of years while stuck in the pocket dimension, likely done to differentiate him from Clark Kent and Lois Lane's teenage son Jon. While Young Justice remembered their past adventures with Superboy, Superman was initially unaware of his history with his clone. To help jog both of their memories, Clark took Conner with him back to Smallville to reunite with Jonathan and Martha Kent tending the family farm. Observing that both he and Conner were raised by the kindly couple, Clark noted that made the two of them brothers as he completely welcomed Kon-El back into the Superman Family, with Conner happily accepting the invitation.
This isn't the first DC hero that Superman has regarded as a brother. The prominent Legion of Super-Heroes member Mon-El was confused as a possible brother of Superman when he first arrived on Earth when Clark was still a boy. Suffering from amnesia while boasting the same superpowers as Clark, Mon-El's memories as a Daxamite were restored when he accidentally endured lethal lead poisoning, necessitating his exile into the Phantom Zone to go into a state of stasis until Brainiac 5 could arrive years later with a cure. Even after the truth of Mon-El's background was revealed, the superhero still maintained a close relationship with the Man of Steel as a surrogate brother.
Conner Kent is now officially reintegrated into the Superman Family, not just as an ally and clone of the Man of Tomorrow, but taking on a different familial role as Clark Kent's younger brother just in time for the DCU to face a new cataclysmic change as it moves into the Infinite Frontier era. With this last little reunion right in the heart of Smallville, Conner Kent's reintegration into the wider DCU is complete as he moves into the future now finally fully recalling his past. The Superman Family is one of the tightest ensembles in the DCU, and now with Conner embraced as a literal brother, the iconic heroes are even stronger together.