Although Young Sheldon’s series finale may have explained a lot of the show’s canon inconsistencies, The Big Bang Theory’s spinoff still left a few mysteries unresolved in its final outing. Young Sheldon’s series finale finally brought the show’s story full circle by skipping ahead in time. The finale revealed an older Sheldon putting the finishing touches on his memoir. In the process, Young Sheldon gave viewers a glimpse of what his life was like after The Big Bang Theory’s finale. Sheldon and Amy’s children were mentioned, as was The Big Bang Theory’s Penny. Leonard, notably, went unmentioned.

This prompted a flurry of fan theories online as viewers wondered whether Sheldon’s failure to reference his friend meant that Young Sheldon’s series finale killed off Leonard. While this is a possibility, it is more likely that the series simply didn’t have enough screen time to discuss what Leonard has been up to since The Big Bang Theory ended. After all, Howard, Raj, and Bernadette are never mentioned in the show’s final episode. Even some of Young Sheldon’s own storylines were left unfinished, resulting in plot holes that opened a gap between The Big Bang Theory and Young Sheldon.