The sixth season of Young Sheldon premiered on September 29, 2022, which will continue to lead up to the events of The Big Bang Theory. The original series may have ended in 2019, but its popularity still remains, as fans continue to look back at the many characters on the show.

However, certain characters didn’t receive the complete ending that most others did. This is due to the lack of information about their whereabouts, ranging from former love interests like Stephanie Barnett to workplace people such as Colonel Richard. It’s worth checking out why they were important enough to remember and why it's so jarring that these characters didn’t get a proper send-off.

Leslie Winkle Was Phased Out

Leslie is one of the notable relationships Leonard had in The Big Bang Theory since she was his first on-screen girlfriend. After featuring in romances with Leonard and Howard, along with a rivalry with Sheldon, Leslie simply disappeared without explanation for years.

She reappeared for Sheldon’s birthday in the ninth season, but there was no update on what she was up to or even why she was there. Leslie vanished once again after this episode to never be mentioned again, which is strange given that dating her was a big part of both Leonard and Howard’s backstory.

Missy Cooper's Relationship Status Remains Unclear

Missy is among the funniest characters in Young Sheldon as the complete opposite of her twin. But the older version in The Big Bang Theory was largely sidelined. She wasn’t technically forgotten because Sheldon mentioned her in his Nobel Prize-winning speech, but that was the most fans heard of her.

Viewers were never told of what her actual status was, seeing as Missy was last seen pregnant and going through a divorce at the same time. Given her importance to Sheldon in the earlier seasons and Young Sheldon it's a shame her story line was never resolved.

Alfred Hofstadter's Romance With Mary Was Unresolved

Leonard’s father was set up with a romance with Sheldon’s mother in the ninth season finale, which was hinted at in the following season’s premiere. However, this was the last time that Alfred was ever seen on the show, with the character only occasionally mentioned afterward.

But Alfred wasn’t even brought up during the final episode featuring Leonard’s mother, which brought him closure over his childhood. Leonard wasn’t shown deliberating over his father’s influence in his life as his mother had, nor was there an update on what happened between Alfred and Mary Cooper to nicely round off the character.

Issabella's Relationship With Raj Was Unexplored

Issabella appeared in just one episode, but it was meant to show the development of Raj’s character as he matured and became less spoiled, humbled by her straight talking. After this major change, though, Issabella simply disappeared, with just one indirect mention later on when Raj claimed his girlfriend had dumped him.

Unlike Raj’s other exes such as Lucy, Emily, and Claire, he wasn’t shown pondering over what went wrong with Issabella or achieving closure over their relationship. Issabella wasn’t mentioned again after the offhand remark by Raj either, as if the romance never happened.

Colonel Richard Williams' Projects Were Quietly Dropped

Colonel Richard was the person that Howard, Sheldon, and Leonard communicated with in regard to their government project, The task itself was phased out, with the final appearance of the character surrounding the guys’ attempts to win his favor for another project.

After this, Colonel Richard wasn’t seen again, with no mention of Leonard, Howard, and Sheldon’s work under his department. The last season dropped this in favor of Sheldon’s Nobel Prize-winning research with Amy, leaving Colonel Richard’s status up in the air.

Stephanie Barnett's Break Up With Leonard Was Never Addressed

Stephanie’s arrival brought the most major relationship in The Big Bang Theory at the time, as she essentially moved in with Leonard. He was clearly uncomfortable with how fast things were moving but wasn’t brave enough to confront her about it.

However, this arc was dropped immediately in the next episode, with Stephanie never being brought up again after Leonard breaks up with her via text. In fact, Leonard didn’t recall her among his previous romances later on, with even his one-time fling Joyce Kim getting a mention over Stephanie. The lack of recalling such a big relationship in Leonard's life seems like a really strange and obvious gap in The Big Bang Theory.

Priya Koothrappali's Life In India Wasn't Shown

Priya had a major role in the fourth season where she appeared in the majority of episodes because of her relationship with Leonard. She was still acknowledged after she moved back to India, but her unfaithfulness to Leonard ended their relationship and her time on the show.

She was indirectly mentioned in the tenth season when Raj’s father mentions that all his children apart from Raj are married, which indicates that Priya may have gotten hitched. However, Priya isn’t mentioned by name after breaking up with Leonard, nor was there any indication of what she did in India. Leonard wasn’t even shown to be impacted by their split despite having dated her for about a year, when other times he was shown to be devastated.

Alex Jensen's Career Ambitions Remain Unclear

Alex brought some conflict into Leonard and Penny’s relationship during the sixth season when she was clearly attracted to him. This was segued into another story, though, where Sheldon unknowingly was inappropriate toward her when he addressed her attraction to Leonard.

Alex wasn’t seen again following this story, with Leonard and Penny evidently getting over her presence – Sheldon was once again seen working on his own rather than having an assistant. Alex was introduced as attempting to progress in her career, but this wasn’t addressed, and she wasn’t seen at Caltech again.

Mrs. Koothrappali's Life After Divorce Wasn't Shown

Mrs. Koothrappali was relevant when she and her husband were still together and communicating with Raj. She was only seen one more time after their divorce, which took place back in the eighth season. Unlike her ex-husband, who even appeared in person afterward, Mrs. Koothrappali was phased out.

Raj mentioned that his father was back in the dating scene, with the latter also continuing to be seen in video chats. But his mother’s status was still up in the air as of her last appearance, as Mrs. Koothrappali wasn’t mentioned again, and the show seemed to have forgotten about her.

Ramona Nowitzki's Time At Caltech Is A Mystery

Ramona disappeared twice during the series’ lifetime, with her second being more of a mystery. She returned as part of the arc that proved why Sheldon and Amy were couple goals in The Big Bang Theory, as her move on Sheldon reconfirmed to him that he needed to marry Amy.

Ramona was briefly confronted by Amy, who ended up thanking her for her indirect part in getting Amy and Sheldon engaged. However, the fact that Ramona was now supposed to be at Caltech around Sheldon full-time was never addressed – it even seemed as if she didn’t work there anymore despite having recently joined. Ramona’s arc with Sheldon was effectively dropped and forgotten by the end, seemingly only existing to serve as a motivator for Sheldon's proposal.

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