Lee and his family released a statement saying Joan Lee died peacefully Thursday morning. The couple had been married 69 years.
Lee’s longtime publicist Dawn Miller confirmed the statement’s authenticity when contacted by the Associated Press but no additional details were provided and the statement requested privacy.
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Joan had reportedly been hospitalized after suffering a stroke earlier this week, according to Variety.
Stan Lee co-created numerous Marvel Comics superheroes including Spider-Man, the Fantastic Four and the X-Men.
Joan Lee, a former hat model, appeared alongside her husband in his cameo in X-Men: Apocalypse and she lent her voice to a number of animated Marvel projects including The Spider-Man, Fantastic Four, and Iron Man cartoons from the 1990s.
Joan also published a novel in 1987 titled, The Pleasure Palace, about a man striving to build the most luxurious ocean liner ever while romancing several women at once.
The Hollywood Reporter, which first reported Joan Lee’s death, recounted the couple’s first meeting in a story last year. It said Lee met his future wife while trying to meet another woman for a date in New York. The couple was married in December 1947 and had two daughters, one of whom died days after being born.
The 94-year-old Lee has credited his wife with supporting him early in his career when he was trying to create superheroes that he and others could care about.
Marvel has released a statement offering thoughts and prayers to the Lee family.
“We lost a member of the Marvel family today and our thoughts and prayers go out to Stan and his daughter Joan in this difficult time,” Marvel wrote.
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More condolences started pouring in on Twitter once news of her passing spread.
We are sending our condolences and prayers to @TheRealStanLee on this sad day.
— Hugh Jackman (@RealHughJackman) July 7, 2017
Rest in Peace #JoanLee, beloved wife of @therealstanlee. Back in January, I got to interview this amazing woman for a @legionmofficial VR look-back at Stan's career. I'll never forget the moment she said "It's always Spider-Man, Spider-Man, Spider-Man. They don't know the amazing writer he really is." She then talked about the words her longtime love had written for her over a lifetime spent together. There's a very famous story about Stan wanting to leave @marvel, in which Joan advises him "Before you quit, write a comic you're proud of." That comic was #fantasticfour – the birth of the #marvel Universe. He told us tales of heroes but Joan was Stan's personal superhero – and without her, we never get our modern mythology. They say behind every great man is a great woman. In this case, the great woman was always standing right beside him. Joan and Stan were best friends for 70 years. My heart goes out to my hero Stan, his daughter JC, their right hand Max and anyone who ever met Joanie. Thank you, Marvel Muse. We'll miss you, Madame Web. #StanLee #KevinSmith
RIP Joan Lee, 93, beloved wife & muse of Stan Lee since 1947. pic.twitter.com/PrBJ5rVDsK
— 9GAG (@9GAG) July 7, 2017
Deepest sympathy to Stan Lee for losing his wife Joan after 70 years of marriage. Love from all his fans. #SpiderManHomecoming
— chaplinlives (@chaplinlives) July 7, 2017
We would like to extend our deepest condolences to Stan Lee and his family at the passing of his beloved wife Joan Lee.
— San Diego Comic-Con (@Comic_Con) July 6, 2017
RIP Joan Lee, 93, beloved wife of Stan Lee since 1947. pic.twitter.com/axJsTaKVLf
— Jake Tapper (@jaketapper) July 6, 2017
— Brett Dalton (@IMBrettDalton) July 7, 2017
Sending my sincerest condolences to @TheRealStanLee on the passing of Joan. All of your Avengers are holding you&your family in our prayers.
— Chadwick Boseman (@chadwickboseman) July 6, 2017
Behind every great creator is an incredible partner. We are heartbroken by the passing of Joan Lee. Sending love to Stan Lee and her family. pic.twitter.com/ix6TWclMIE
— Wizard World (@WizardWorld) July 6, 2017
—With files from The Associated Press