The Winchesters are eventually able to banish Lucifer to a parallel universe where the Apocalypse took place 'on schedule', in 2012, but this plan backfired when Lucifer alerted the alternate version of Michael to the existence of the original world, as well as leaving them with the complication of trying to raise Lucifer's suddenly-adult son, Jack Kline (6 months old, chronologically). Jack soon comes to see the Winchesters and Castiel as his 'fathers', while they gain a new ally when they discover that Gabriel survived his death, in season 5, but although they are able to return to the Apocalypse World to rescue several humans (including alternate versions of Bobby Singer and Charlie Bradbury), the alternate Michael, and Lucifer follow them into this world.