Warning! Young Sheldon season 6, episode 20. Young Sheldon season 6, episode 20 changes Missy's The Big Bang Theory appearances for the worse. Like most of Sheldon's family, his sister was already an established character before Raegan Revord debuted the character in the prequel. After Mary, Missy was the second member of the clan to make a physical appearance on the geek-centric sitcom. The rest of the Pasadena gang marveled at how different she was from the crabby Sheldon. Despite her great rapport with The Big Bang Theory cast, however, she wouldn't be back on the show until a decade later for Sheldon's wedding in season 11.

Despite her brief involvement in The Big Bang Theory, Missy clearly made her mark, which is proven by her continued popularity in the prequel. It helps that George and Mary's only daughter has proven time and time again that not only is she loyal but also highly dependable. While she isn't immune to making mistakes, she hasn't done anything beyond the stereotypical teenager gaffes. Young Sheldon season 6 has only featured Missy sporadically, but she still manages to be a scene-stealer, highlighting just how good her character is. However, the prequel may have exposed Missy's bad side that recontextualizes her The Big Bang Theory appearance.

Related: Young Sheldon Season 6 Surprisingly Fixed Its TBBT Germany Plot Hole

How Big Bang Theory’s Missy Is Different From Young Sheldon’s

Courtney Henggeler is Missy Cooper in The Big Bang Theory

While Young Sheldon has long broken away from The Big Bang Theory, both shows officially still exist in the same reality. Arguably their biggest narrative inconsistency is the depiction of George Cooper, but the rest of the family are also very different in the nerd-centric sitcom. That includes Missy. Despite not being intellectually gifted like Sheldon, Missy has proven time and time again that she is the best Cooper, as not only is she charming and witty, but she's also fiercely loyal and emotionally mature for her age. Unfortunately, The Big Bang Theory painted a bleak future for her, becoming the least successful Cooper sibling.

Aside from giving her an undeserved The Big Bang Theory life, it's also worth noting that Missy is spunkier, sassier, and overall more dynamic as a character in Young Sheldon. When she appeared in the nerd-centric sitcom, she was nice, gracious, and even very sweet to Sheldon. As touching as it was seeing her be nice to her twin, it doesn't line up with her dynamic with her twin in the prequel.

Young Sheldon Suggests Missy Was Faking It In Big Bang Theory

Missy waving hello in TBBT

While there is no doubt that Missy is kind, Young Sheldon season 6, episode 20, "German For Beginners and Crazy Old Man With A Bat," suggests that she was faking it in The Big Bang Theory. After realizing that getting into Caltech's post-grad program isn't going to be a walk in the park. Dr. Sturgis helped him get into the University of Heidelberg's summer program but it isn't fully funded. He is about to lose hope, but when Missy finds out about this, she convinces him into thinking that he needs to push for this endeavor. However, this isn't because she supports Sheldon, but because she wants him gone.

Missy does this quite naturally, making her believable. Granted that Sheldon isn't known about recognizing subcontext, but it's still sad to see him easily be convinced that his sister wants the best for him. This isn't the first time that Missy uses her social skills to get what she wants, but considering what's happening to her twin, it's difficult to not feel bad about it. If she's able to easily do this in Young Sheldon, it isn't outside the realm of possibility that Missy also dialed up her charm when she first visited Sheldon in Pasadena to win the affection of his friends.

Why Young Sheldon Season 6 Is Ruining Missy

Missy and Sheldon in a fight in the Young Sheldon season 6 finale

Given Missy's popularity, it's odd that Young Sheldon opted to sideline her for the longest time. While she has been a great supporting character, it's frustrating that she has barely had any arc of her own in season 6. Suffice it to say, ignoring her has been the biggest mistake that CBS has committed in The Big Bang Theory prequel. Towards the end of the year, however, Young Sheldon tried to rectify that issue by shifting the spotlight on her. Unfortunately, instead of giving Missy regular lighthearted narratives, the project seems keen on ruining the character.

While Georgie did describe her as a "dumb teenager" in The Big Bang Theory, there was an assumption that her rebellious phase started after George's death. Now, however, it appears as if she was already down a dark path long before the Cooper patriarch's demise. For what it's worth, the fact that George and Mary continue to fail to address her issues of feeling overlooked and neglected means that they are a big part of the problem. Aside from grounding after she tried running away to Florida with Paige, they haven't properly talked to her about what both parties can do to solve the issue moving forward.

Related: Young Sheldon's Original Villain Is About To Make Missy's Future So Much Worse

Can Young Sheldon Season 7 Still Redeem Missy?

Missy looking at George in Young Sheldon season 6

Details for the Young Sheldon season 6 finale suggest that the two-episode send-off will heavily focus on Sheldon as he and the rest of the family prepare for his trip to Germany. That being said, several promotional videos for the special one-hour finale reveal that a serious fight between Missy and Sheldon is about to happen. No details have been shared about what the issue will be, but surprisingly, it's the socially-inept genius who is apologetic about the issue. Whether they will patch things up before his trip is currently unknown.

With Young Sheldon season 7 already guaranteed, CBS still has time to redeem Missy after her string of mistakes towards the end of season 6. Unfortunately per The Big Bang Theory canon, this is unlikely. The only Cooper daughter will continue going down the dark path, exacerbated by the death of George and the arrival of Pastor Jeff's no-good niece, Tonya.

Young Sheldon season 6 airs Thursdays on CBS.