Warning! Spoilers ahead for Young Sheldon season 5.
CBS' Young Sheldon is suggesting that Mary (Zoe Perry) is to blame for Missy's (Raegan Revord) tragic fate in The Big Bang Theory. Sheldon's (Jim Parsons) mom and sister were the first members of the Cooper family to appear in the nerd-centric sitcom. But while Mary's appearance established her close relationship with the socially-inept genius, Missy's cameo highlighted how different her life was from Sheldon's.
Mary appeared regularly throughout The Big Bang Theory's 12 seasons. Missy, on the other hand, despite being referenced a handful of times, didn't return to Pasadena until Sheldon and Amy's wedding in The Big Bang Theory. In the decade in-between her appearances, Missy had undergone several changes in her life. That included getting married and having a kid, with another one on the way. Unfortunately, as her twin was on the brink of starting a marriage, hers was near its tail end. It did seem, however, that Missy had accepted the reality of her situation.
Not much was revealed about Missy's husband or the kind of relationship they had. But, during her final The Big Bang Theory, it was clear that she was ready to move on and push forward with their separation — as if their marriage had long ended. Mary, on the other hand, was in denial; trying to make it seem like their relationship was still salvageable. Going back a couple of decades earlier in Young Sheldon, Mary's worries about Georgie's (Montana Jordan) predicament as a soon-to-be young father suggests that she could be to blame for Missy's miserable married life in The Big Bang Theory. As seen in the ongoing CBS' ongoing comedy, Mary is more than willing to ignore red flags to keep up with appearances. It's possible that Missy would’ve left her husband a long time ago if it wasn’t for her mom’s meddling.
It's clear both in The Big Bang Theory and Young Sheldon that Mary and Missy don't have the best relationship. The pair typically bickers in the spin-off, with Mary having the tendency to underestimate her daughter, while Missy has a penchant for antagonizing her mother. Just in Young Sheldon season 5, episode 19, while she and Sheldon (Iain Armitage) discussed the possibility of their parents divorcing, Missy chooses to live with George (Lance Barber) instead of joining her twin with their mom. Unfortunately, with George's nearing death, she won't have a choice but to stay close to Mary. Unfortunately, per The Big Bang Theory, it doesn't seem like the Cooper family tragedy will bring them closer.
Missy's life may be in shambles when she last appeared on The Big Bang Theory, but CBS has revealed what happens to her beyond that. In a previous Young Sheldon episode, adult Sheldon's narration reveals that she eventually lives a happy life. While the voice-over confirmed that she gets more kids, there was no mention of her love life.
Young Sheldon season 5 airs Thursdays on CBS.