While Day is known for her cinematic and singing achievements, including Alfred Hitchcock's 1956 film, The Man Who Knew Too Much, and for the major box office success of her romantic comedies with the late Rock Hudson -- 1959's Pillow Talk, 1961's Lover Come Back and 1964's Send Me No Flowers -- here are five things you might not have known about the late Hollywood star.
She didn't know her correct age until 2017:
Day thought she would be turning 93 in 2017, but the Associated Press obtained a copy of the actress' birth certificate from Ohio's Office of Vital Statistics, which confirmed that Day was born on April 3, 1922, in Cincinnati, making her actually 95.
"I've always said that age is just a number and I have never paid much attention to birthdays," Day said in a statement to The Hollywood Reporter. "But it's great to finally know how old I really am!"
Day's age has long been speculated, with various news outlets often estimating her age. "We get this question a lot, looks like we finally have the answer," the actress' spokesperson, Charley Cullen Walters, told THR. "The story I have heard the most is that at one point Doris was up for a role when quite young and her age may have been miswritten on the audition form. We don't know if that's correct, but if so it could've simply stuck for all these years."
She wasn't a fan of her innocent image:
Day was well known for playing innocent, chaste characters, causing some critics to dub her "the World's Oldest Virgin." The actress addressed this in her 1976 book, Doris Day: Her Own Story, in which she discussed her three failed marriages: her first marriage to trombonist Al Jorden, with whom she had a son, Terry, her second marriage to saxophonist George William Weidler and her third marriage to Martin Melcher, who became her manager. After Melcher died of heart disease in 1968, Day discovered that his failed investments left her deeply in debt. She eventually won a multimillion-dollar judgment against their lawyer.
She ended up marrying a fourth time to Barry Comden in 1976, but they divorced in 1982.
"I have the unfortunate reputation of being Miss Goody Two-Shoes, America’s Virgin, and all that, so I'm afraid it's going to shock some people for me to say this, but I staunchly believe no two people should get married until they have lived together," she said in her tell-all, via PBS.
"My public image is unshakably that of America’s wholesome virgin, the girl next door, carefree and brimming with happiness," she also said in the book, via The New York Times. "An image, I can assure you, more make-believe than any film part I ever played. But I am Miss Chastity Belt, and that's all there is to it."
She didn't believe she was attractive:
A 2008 Vanity Fair article talked about Day's apparent insecurities, including confronting Hitchcock because she mistakenly thought he was unhappy with her work while filming The Man Who Knew Too Much. Director Norman Jewison, who worked with Day on 1963's The Thrill of It All and Send Me No Flowers, also talked about Doris' surprising view on her obvious good looks.
"Doris did not believe that she was an attractive woman," Jewison said. "I thought she was beautiful. Millions of fans thought she was beautiful. Everybody she had ever worked with thought she was beautiful. Doris remained unconvinced."
Her The Thrill of It all and Move Over, Darling co-star, James Garner, also said of Day: "I'd rather have Doris than Liz Taylor. Everything Doris does turns to box-office gold... I think Doris is a very sexy lady who doesn't know how sexy she is. That's an integral part of her charm."
She actually didn't sign up for her own TV show, The Doris Day Show:
Melcher committed Day to her television series, The Doris Day Show, without her knowledge. She revealed the bombshell in her tell-all and said she only discovered this after he died.
"It was awful," Day told OK! Magazine in 1996. "I was really, really not very well when Marty passed away, and the thought of going into TV was overpowering. But he'd signed me up for a series. And then my son Terry took me walking in Beverly Hills and explained that it wasn't nearly the end of it. I had also been signed up for a bunch of TV specials, all without anyone ever asking me."
The CBS show turned out to be a success and had a five-year run from 1968-1973.
Her late son, record producer Terry Melcher, once turned down Charles Manson:
Day's son Terry, who ended up taking the last name of her third husband, became a successful songwriter and record producer in his own right, working with such musicians as The Beach Boys. He also became known for turning down late cult leader Charles Manson when Manson auditioned for him after he was initially interested in recording Manson's music. The two eventually cut ties.
In a more ominous turn of events, Melcher and his girlfriend at the time, Murphy Brown star Candice Bergen, once lived at the home that became the infamous site of the 1969 murder of actress Sharon Tate and her four friends by Manson and his associates. Melcher and Bergen had already moved out by the time of the murders.
Melcher died in 2004 after a long battle with melanoma. In 2011, Day talked to Reuters about her song, "My Buddy," being about her late son.
"He really was my buddy," Day said of her only child. "I wanted that song to be there because it was for him and, well, all I can say is that I miss him very much."