Young Sheldon has seemingly fixed a major plot hole for The Big Bang Theory in its latest episode.
The spin-off, which focuses on the exploits of a young Sheldon Cooper (Iain Armitage) prior to the events of The Big Bang Theory, is currently midway through its sixth season.
A recurring plotline in Young Sheldon has been Sheldon's mentorship at the hands of John Sturgis, a college physics professor played by Wallace Shawn.
The character was conceived for Young Sheldon and did not appear in The Big Bang Theory, but is shown to be a key guiding figure in Sheldon's life and studies.
In the final season of The Big Bang Theory, we see Sheldon (played as an adult by Jim Parsons) win the Nobel Prize in Physics.
However, fans of the series had called out the fact that Sturgis is incongruously never thanked or mentioned by Sheldon in his acceptance speech, or elsewhere on the show.
Now, the latest episode of Young Sheldon, season six episode 18 ("Little Green Men and A Fella's Marriage Proposal"), may have offered an explanation for the oversight.
In the episode, Sheldon is seen "dismissing" Sturgis as his mentor amid a dispute over the search for extra-terrestrial life.
Sheldon then partners with another professor to aid him in his research. As posited in a theory by Screen Rant, this "dismissal" could provide an explanation for Sturgis's absence in The Big Bang Theory: despite their early relationship in Texas, Sheldon simply no longer considers him a mentor.
Last month, The Big Bang Theory's co-creator Chuck Lorre announced that another spin-off based on the hit sitcom is currently in development.
Plot details are currently being kept under wraps.
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