The Big Bang Theory: Why Kathy Bates Replaced The First Actress Cast As Amy's Mom

There's nothing quite as momentous as a sitcom wedding, and "The Big Bang Theory" pulled out all the stops for Sheldon (Jim Parsons) and Amy's (Mayim Bialik) wedding on the Season 11 finale, "The Bow Tie Asymmetry." Sci-fi bigwigs Mark Hamill and Wil Wheaton join the proceedings, and Jerry O'Connell and Laurie Metcalf reprise their roles as Sheldon's family members. It also marks the on-screen introduction of Amy's parents, played by famed magician Teller and Oscar-winning actress Kathy Bates.

The wedding episode isn't the first time Amy's mother appears. In Season 4's "The Desperation Emanation," Annie O'Donnell plays Mrs. Fowler in an off-screen Skype call. So why did the actress change? According to "Big Bang Theory" showrunner Steve Holland, the casting of Mrs. Fowler was more or less an afterthought when Amy's role was still being explored. Over time, it became clear that Amy — and, by extension, her family — would become a primary character. "When we had the chance to bring [Mrs. Fowler] back in a role that could possibly recur [we decided to make a change]," he explained to TVLine.

"The Big Bang Theory" enlists notable talent to play the main characters' parents, including Metcalf, Christine Baranski, Judd Hirsch, Keith Carradine, and Katey Sagal. Luckily, co-creator Chuck Lorre had a working relationship with Kathy Bates.

As the creative engine behind "Cybill," "Dharma & Greg," and "Two and a Half Men," among other series, Chuck Lorre has established a thick rolodex of celebrity contacts throughout his career. In 2012, he teamed up with Kathy Bates — known for her varied roles in "Misery," "Titanic," and "The Waterboy" — for "Two and a Half Men." She guest-starred in a Season 9 episode, earning her first Emmy award for the performance.

The role proved to be the beginning of a fruitful partnership between Bates and Lorre, and in 2017, the Bates-starring sitcom "Disjointed" premiered on Netflix. She plays cannabis activist Ruth Whitefeather Feldman, who runs a dispensary in Los Angeles. The show was canceled after one season.

"Disjointed" may have gone up in a cloud of smoke, but it is part of why Lorre tapped Bates for "The Big Bang Theory." "[Chuck Lorre] had a relationship with Kathy Bates after they worked together," Steve Holland confirmed in the same TVLine interview. He also added that Bates' star power didn't hurt her chances. "And, well, how do you say no to bringing Kathy Bates on?"

Overbearing and cautious, Mrs. Fowler is the polar opposite of Bates' carefree role in "Disjointed." She ultimately played Amy's mother for three episodes.