Big Bang Theory actress Carol Ann Susi, who played Howard's mother Mrs Wolowitz, has died after a brief battle with cancer. The actress was unseen by viewers of the show, but her idiosyncratic voice and comedic timing was crucial to many of the sitcom's storylines.

Carol Ann SusiCarol Ann Susi played Howard's [R] overbearing mother - never seen by viewers.

In a joint statement, executive producers Chuck Lorre, Steven Molaro and Bill Prady said: "The Big Bang Theory family has lost a beloved member today with the passing of Carol Ann Susi, who hilariously and memorably voiced the role of Mrs. Wolowitz.

"Unseen by viewers, the Mrs. Wolowitz character became a bit of a mystery throughout the show's eight seasons. What was not a mystery, however, was Carol Ann's immense talent and comedic timing, which were on display during each unforgettable appearance.

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"In addition to her talent, Carol Ann was a constant source of joy and kindness to all. Our thoughts and deepest condolences are with her family during this time, and we will miss her greatly."

First discovered by the casting department at Universal Studios in Los Angeles, Susi appeared in dozens of critically acclaimed shoes including Seinfeld, Six Feet Under and Cheers, as well as Mad About You, Just Shoot Me and Doogie Howser. 

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On the big-screen, she also appeared in Death Becomes Her, Cats & Dogs and the comedy Just Go With It, with Jennifer Aniston and Adam Sandler.

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A representative for the actress also released a tribute.

"A spunky Italian gal from Brooklyn whose passionate interests included Doctor Who, Halloween horror mazes, cooking and the Magic Castle, Carol Ann drew fervent circles of followers," it read.

"She has a force of nature who didn't suffer fools and was fiercely loyal to her friends. Known only to a very lucky few, she was a world-class culinary genius who frequently scored blue ribbons at the very competitive cooking competitions at the Los Angeles County Fair."

Carol Ann Susi is survived by her brother, Michael.

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