The Doris Day Animal Foundation confirmed the news early Monday morning in a press release. The foundation wrote that Day "had been in excellent physical health for her age, until recently contracting a serious case of pneumonia, resulting in her death."
The actress-singer died at her home in Carmel Valley, California, and was "surrounded by close friends as she passed."
Day, born in 1922 as Mary Ann Von Kappelhoff in Cincinnati, Ohio, was known for her work in 39 films that included dramas, musicals and comedies throughout the 1950s and '60s. Her most notable films included Calamity Jane and The Pajama Game. Musically, Day was known for hits such as "Sentimental Journey" and "Que Sera Sera."
As for her accolades, Day was honored with the Cecil B. DeMille Award in 1989, the Presidential Medal of Freedom in 2004 and a GRAMMY for lifetime achievement in 2008.
Day had 11 nominations and four wins at the Golden Globes, two GRAMMY nominations and one Oscar nomination for her role as Jan Morrow in Pillow Talk in 1959. Additionally, three of her songs -- "Sentimental Journey," "Que Sera Sera" and "Secret Love" -- were inducted into the GRAMMYs Hall of Fame.
Day was also passionate about her work with animals, fighting against animal testing and for spay/neuter education and outreach programs through her foundation, which has a special focus on assisting senior pets. While Day's wishes indicate that she have no funeral, service or grave marker, fans are encouraged to support to the foundation in her memory.
Day was married four times throughout her life, most recently to Barry Comden, whom she split from in 1982 after more than five years of marriage. She had one son, Terry Melcher, whom she shared with her first husband, Al Jorden. Melcher, a musician, died in 2004 at age 62 after a battle with melanoma.