McGuire's daughter, Topo Swope, says the actress broke her leg three weeks ago and developed heart failure.
"She had a wonderful life and accomplished a lot," Swope tells the Associated Press. "She went very peacefully."
McGuire earned an Oscar nominated for Gentleman's Agreement, the groundbreaking movie about religious and cultural prejudice, and a trio of Emmy nominations, most notably for the acclaimed miniseries Rich Man, Poor Man.
While she was known for her family films, her ability to appear either glamorous or drab, naive or strong-willed brought her wide-ranging success.
She was once described in a magazine article as "a pug-nosed, slightly blonde version of Garbo." It was an inaccurate physical description but did somehow touch on the inner strength she was able to project on screen.
She never really liked to talk about her acting, and, although always full of praise for her costars, she reserved her highest accolades for her late husband, John Swope. She was married to the Life photographer for many years and her eagerness to travel with him around the world meant that her roles, though carefully chosen, were less numerous than they might have been. "I was very lucky in the film material sent me, but sometimes I preferred being in the theater and other times going traveling with John," she said in recent interview.
Born in Omaha, she made her stage debut as a young girl opposite Henry Fonda (who became a lifelong friend) in a local stage production of A Kiss For Cinderella. In 1938, she took over the role of Emily in the Broadway production of Our Town and then achieved stardom as the naive young wife in Claudia, a role she reprised in the Hollywood movie opposite Robert Young.
She also starred opposite Young in the sequel Claudia and David and the romantic fantasy The Enchanted Cottage, in which love transformed her character from dowdy to beautiful, a trick she achieved without the help of any special make-up.
Her other leading men included Gary Cooper (Friendly Persuasion) and Gregory Peck (Gentleman's Agreement). Other screen credits included A Tree Grows in Brooklyn (1945), the first time she was cast as a mother, and The Greatest Story Ever Told (1965), in which she played the Virgin Mary.
She is survived by her daughter and her son, artist and photographer Mark Swope of Los Angeles.