WARNING: The following contains major spoilers for Crisis on Infinite Earths, Part 2,” which aired Monday on The CW.

One of the biggest revelations in the "Crisis on Infinite Earths, Part 2" episode that played out in Batwoman on Monday night was that Brandon Routh's Superman wasn't just from Kingdom Come, he was actually continuing from Superman Returns, already a continuation of Christopher Reeve's films. Now, courtesy of Arrowverse showrunner Marc Guggenheim, we know what happened to his son, Jason.

"Of course Jason is alive," Guggenheim tweeted, "He wasn't at the Planet." This was in response to fans who wanted to know the fate of the boy as it was revealed Lois Lane, Perry White, Jimmy Olsen and the rest of the Daily Planet was gassed to death by Joker. This is what drove Routh's Superman to battle Tyler Hoechlin's Superman when Lex Luthor corrupted the former.

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Routh's Kal-El did mention Jason when holding Hoechlin Kal-El's baby, Jon, but it wasn't clear if the kid died in the Planet attack too. In Superman Returns, Jason was a controversial topic as Lois withheld the truth about Superman being his dad from the Man of Steel himself.

By movie's end, while Superman's not an absentee dad anymore, Lois remained with Perry's nephew, Richard. Now that fans know Jason's alive, they're wondering what the boy's up to years after his mom and step-father died.

"Crisis on Infinite Earths" will return after the winter hiatus. The crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.

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