Marshall's publicist, Michelle Bega, confirmed the star's death on Tuesday, telling the New York Daily News that Marshall passed away "peacefully" at her home in Hollywood on Monday night, from complications from diabetes.
The star's family also released a statement about her passing, referencing the famous monogrammed wardrobe she sported as her "Laverne & Shirley" character, Laverne De Fazio.
“Penny was a girl from the Bronx, who came out West, put a cursive ‘L’ on her sweater and transformed herself into a Hollywood success story,” the statement said.
Marshall was the younger sister of the late writer-director-producer Garry Marshall, and it was her brother's influence that helped her land her most famous role. Garry cast Penny and Cindy Williams as Laverne and Shirley on his wildly popular sitcom, "Happy Days," and the pair later got their own eponymous spinoff series. "Laverne & Shirley" ran for eight seasons on ABC, from 1976 to 1983, and gave Penny Marshall the directing bug, with the actress helming several episodes of the sitcom.
Her first feature directing gig came in 1986, on the Whoopi Goldberg comedy "Jumpin' Jack Flash," and Marshall's success snowballed from there. She went on to helm many more films, including the Tom Hanks classic "Big," which became the first female-directed film to gross $100 million domestically. Later, she reunited with Hanks for the groundbreaking All-American Girls Professional Baseball League comedy "A League of Their Own," and also directed the Robert De Niro-Robin Williams drama "Awakenings," which received a Best Picture nomination.
Marshall also starred in classic sitcoms including "That Girl," "The Odd Couple," "The Mary Tyler Moore Show," and "The Bob Newhart Show," and had minor roles in films including Steven Spielberg's "1941" and "Get Shorty." Her most recent acting gigs included guest starring spots on "Portlandia" and the remake of "The Odd Couple," and her latest directing work included helming episodes of Showtime series "United States of Tara."
Marshall was previously married to actor-director Rob Reiner for 10 years. She's survived by her daughter, Tracy (who starred as Betty Spaghetti in "A League of Their Own"); her sister, casting director and producer Ronny Harlin; and three grandchildren. Her family is planning a "celebration of life" at a later date.