One of the most oddly specific sitcom tropes is the unseen character. These range from Frasier's physically impossible wife of Niels Crane (David Hyde Pierce) Maris to gentler takes on the subject, like Wilson (Earl Hindman) on Home Improvement.

The Big Bang Theory is no exception to the trope's pervasive presence, thanks to Howard Wolowitz's (Simon Helberg) unseen but much-heard mother, Debbie Wolowitz. An abrasive and imposing presence in Howard's life, Mrs. Wolowitz is nonetheless a force for good and an important figure to both him and most of the show's other main characters.

Since the character is, for all intents and purposes, just the voice of "The Big Bang Theory," fans may have noticed a noticeable difference in how he sounds on "Young Sheldon." This isn't because the actress who voices Mrs. Wolowitz on The Big Bang Theory, Carol Ann Suzy, was told to change the character's voice to convey her younger age. The real reason is much more tragic, as Susi actually died in 2014. Because of this, Pamela Adlon voices Mrs. Wolowitz in the prequel series.

Of course, every Big Bang Theory character who appears in the 1980s and '90s Young Sheldon setting had to be recast to avoid the kind of situation in which perma-stubbled 40-year-olds play 13 years old. However, after Carol Ann Soucy died in 2014 at just 62 years old, the situation was very, very different.

The Big Bang Theory never shows Howard's mother, but due to Susie's death, the show never recast her either. Instead, the people behind the show addressed the situation with a touching send-off for the character from Season 8, as Debbie Wolowitz became one of the show's deaths of major characters. In a 2015 interview with The Hollywood Reportershowrunner Steve Molaro addressed the shock of Susie's death and how the show's creatives came to the decision to deal in-universe with Ms. Wolowitz's death:

“It took a while for that devastation to settle down before we could think about it. We couldn't bring ourselves to start thinking about it. plan, and I don't think we could bring ourselves to replace the actor. "The thought of that was horrifying to us and we wrote it into the show, so that's what we chose to do."

The appearance of the character in "Young Sheldon" can hardly be called a transformation. When a montage of The Big Bang Theory as kids in the second season episode "Swedish Science and the Toast Equation" needed a cameo for Ms. Wolowitz, Pamela Adlon simply stepped in to provide the necessary vocal work.