There are a lot of fun character dynamics on display throughout “Young Sheldon,” but I’d argue the most charming is the relationship between Missy (Raegan Revord) and Sheldon (Iain Armitage). They might be fraternal twins, but Missy is bad at school and great with people while Sheldon is, well, the opposite. Yet, even though the two have nothing in common, they’re still there for each other whenever it counts. Take for instance the moment in the season 4 finale, “The Wild and Woolly World of Nonlinear Dynamics,” where Missy wants to run away and Sheldon follows her. 

“I’m sorry, but I can’t let you wander at night by yourself. I’m your big brother,” Sheldon tells her. When Missy points out that they’re twins, Sheldon responds, “I was born two minutes earlier, which apparently makes me responsible for you … I’m not happy about it either, but here we are.” This was a stand-out moment for Raegan Revord, who named it in a 2024 interview as one of her favorite moments in the series: 

“If I had to pick, it would probably be whenever Missy and Sheldon go into that little shack in the woods because Missy is running away. It was really sweet because one of Sheldon’s lines is something like, ‘I’m older by ten minutes, so I have to watch out for you,’ or something like that. I’m like, ‘Oh, that’s so sweet.” It was a fun scene to film off-screen. It’s a fun scene to watch. I love it.”

This moment is particularly sweet given how far apart Sheldon and Missy grow throughout the series. As Sheldon climbs the education ladder while Missy goes through school at a regular pace, the nice moments between them grow fewer and farther between. There’s an extra sense of melancholy here for fans of the show’s parent series, “The Big Bang Theory,” because that show establishes that Sheldon leaves his family for Caltech at only 14 years old, and that he doesn’t see Missy that often from that point forward. By season 4, not only have Sheldon and Missy been growing apart, but we know the problem’s only going to get worse from here. 

“I think one thing that makes the Missy and Sheldon bonding scenes so sweet is that they don’t happen often,” Revord explained in the same interview. “And so whenever you do get a time when Missy is going through something, or Sheldon is going through something, and the other twin is there for them, it really shows that even though they argue, even though they might not see eye-to-eye all the time, they still do love each other.”

When Revord was asked about her character’s favorite relationship throughout the series, she mentioned Missy’s father, George Sr. (Lance Barber). Like with her and Sheldon, there’s an undercurrent of looming tragedy behind Missy and George Sr.’s scenes, and “Young Sheldon” has always made the most of it. As Revord explained:  

“The Missy and George bonding scenes are my favorite thing ever and my favorite to film. George and Missy have the same relationship as my dad and I, and Lance and I have the same relationship as my dad and I, so it’s always so much fun to film. It’s just us being us. … Honestly, any George and Missy scene or episode is my favorite.“