There's no doubt that Young Sheldon came out of the gate with a strong suite of main characters, including Sheldon, his parents Mary and George, siblings Georgie and Missy, and grandmother Connie, who he affectionately called Meemaw through to adulthood. But as the show progressed, new and interesting characters were added to the mix.
Each added their own flare and played a role in Sheldon's life, and/or the lives of those close to him. For some, it's unclear where they eventually ended up, but fans hope to find out via the show's narration from adult Sheldon.
Coach Dale Ballard
Coach Ballard first appeared in an episode as the coach of a local baseball team Missy wanted to . However, when he didn't want to allow her to play, Connie furiously marched her granddaughter back. She explained to him that, regardless of gender, Missy was a talented player and should be allowed on the team.
Coach Ballard not only listened to Connie, who was right as it turned out Missy had a killer pitching arm, but he instantly fell for her and they began dating. While things didn't work out between them, Coach Ballard was an important part of Connie's life and, for a short term, served as a mentor and friend to Georgie as well.
Dr. John Sturgis
Dr. John Sturgis made quite an impact on Sheldon's life, first as a pen pal, then a professor, and eventually, a close friend. While Sheldon found it difficult to relate to his peers, he got along swimmingly with Dt. Sturgis. So, he was pleased when the quirky and eccentric physicist began dating his grandmother and spending a lot more time with the family. Technically, the character was introduced in the first season but didn't become a fixture until after.
The reveal of Dr. Sturgis' mental health issues was particularly tough on Sheldon and marked one of the times Young Sheldon dealt with serious issues. But fans adore the character who remains on the show as a friend of the family. He's arguably the character fans are most curious to find out more about in the future.
Brenda Sparks
Also technically introduced towards the end of the first season, Brenda Sparks was the long-time neighbor of the Coopers. But she's worth mentioning given her character arc on the show. She began as an unfriendly type, arguably the polar opposite of Mary, which caused them to butt heads quite often, particularly when it came to the kids.
But after her husband left her, Brenda mellowed. She not only spent time bonding with Mary, but she later showed a romantic interest in George though neither acted on their feelings. While it's unclear if she is the woman Sheldon eventually catches his father with, her presence doesn't help when it comes to the marital issues George and Mary were experiencing.
Dr. Linkletter
Dr. Linkletter is a colleague of John's at the university and initially only appeared in small doses as he would see John, Connie, and Sheldon at school functions and flirt with Connie, much to both her and John's annoyance.
Later, however, Dr. Linkletter becomes a mentor, of sorts, to Sheldon after John quits science and Dr. Linkletter is reluctantly tasked with keeping an eye on Sheldon while he's away at the university. While he gets increasingly annoyed with Sheldon, after Dr. Linkletter begins to respect the young boy's genius, they collaborate on research.
Gene Lundy
Lundy, one of the best ing characters on Young Sheldon, appears in the first season towards the end, but his role becomes larger as the show goes on. He is introduced as the school drama teacher who seems far too involved in his role, trying to live out his dreams vicariously through the kids.
Played by Seinfeld's Jason Alexander, Mr. Lundy appears in several more episodes, including a Halloween themed one where he battles with Mary to create a theatrical haunted house experience for the kids and when he starts selling Mary Kay on the side and enlists Mary to do it as well. He's theatrical, over exaggerated, and brings additional laughs to the show.
President Hagemeyer
ing the show in the later seasons and played by veteran actor Wendie Malik, President Hagemeyer is the president of the university Sheldon attends and is thrilled to have him aboard given his knowledge, skillset, and the attention he brings to the university.
Always pleasant around him, she does her best to keep him happy despite how much he can annoy her. She keeps him busy with meaningless projects and even gave him access to a dorm all to himself just to keep him from irritating her. The dynamic between President Hagemeyer and Sheldon is one of the best among the new seasons.
Paige Swanson
Paige's story is one that is being expanded in the later seasons, making fans even more curious about where she might be today. Introduced as a young child prodigy like Sheldon, who is one of the smartest child geniuses on TV, he was initially angered at the fact that she might even be smarter than him. As they got older, however, a fractured home life made things difficult for Paige, who began to act out. She wouldn't apply herself and went through a period of rebellion.
Later, when she discovered Sheldon had actually made friends in university and was having a blast while she spent nights at her school alone in her dorm, she became jealous of him. The character, being the same age as Sheldon, has fans dying to know what happened to her, how long they kept in touch, and if Sheldon's friendship with her bloomed even further.
June
When Connie started dating Dale, she probably never could have imagined that she would have become close friends with his ex-wife. But that is exactly what happened by complete chance. While the two have shared some conflicts, June, played by Reba McIntyre, is happily single and long divorced from Dale while Connie appreciates having someone her age to confide in.
The episode where Connie and June go out partying together in Las Vegas is one of the funniest and sweetest of the show, and the friendship between the two is as solid as it is hilarious.
Mandy
Fans suspect Mandy will have a larger role to play on the show going forward as the older woman Georgie dated when he lied about his age. But the biggest reason is the reveal that Mandy is pregnant with Georgie's child, which will soon become one of the most questionable parenting choices in Young Sheldon. At just 17 years old, it's clear Sheldon's older brother is about to become a teenage father.
Based on reveals in The Big Bang Theory, Georgie doesn't end up with Mandy long-term as he references having several ex-wives. But fans are interested to see how the relationship goes with Mandy, especially since she had broken up with him as soon as she found out his real age but before she discovered she was pregnant.
Pastor Rob
For a long time, the team at the church was just Mary, Pastor Jeff, and his secretary Pam. But when they realized they needed someone younger and hipper to really get through to the kids during Sunday school, they enlisted the help of Pastor Rob.
His character marks the first time fans see Mary having inappropriate thoughts about another man, which she quickly pushes down, leading to her having racy dreams about him. Sweet, kind, and great with the kids, Mary enjoys spending time with him and the fact that he shares the same values and relationship with God that she does.