Sheldon's (Jim Parsons) experience in Young Sheldon may be the reason why he regularly criticized Penny (Kaley Cuoco) for her relationship choices in The Big Bang Theory. The socially-inept genius continues his story through the CBS spin-off that tackles a portion of his childhood in Texas.
Given this, several aspects of Sheldon's personality are explained in Young Sheldon making fans understand his behavior more in The Big Bang Theory. That potentially includes his strong opposition to Penny's
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