Legendary director and producer Garry Marshall died on Tuesday from complications of pneumonia, ET can confirm. He was 81.

Marshall was one of the pillars of Hollywood, in both the world of film and television, creating hit sitcoms and iconic movies. He also founded the Falcon Theatre in Burbank, California.

In 1970, Marshall made his first indelible mark on the industry when adapted the Neil Simon play The Odd Couple into a long-running, acclaimed TV series of the same name, starring Tony Randall and Jack Klugman.

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Four year later, he created the beloved series Happy Days, and later, multiple spin-off series: Laverne and Shirley, Joanie Loves Chachi and Mork & Mindy.

His big screen career was equally prolific, helming celebrated classics such as Pretty Woman (1990), Frankie and Johnny (1991), Runaway Bride (1999), and The Princess Diaries (2001).

Recently, Marshall helmed a series of holiday-themed ensemble rom-coms, starting with Valentine's Day in 2010, followed by New Year's Eve in 2011 and Mother's Day earlier this year. Access Hollywood was the first to break the news of the director’s death.

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ET spoke with Marshall at the New York premiere of Mother's Day back in April, where the iconic filmmaker shared the best advice he's ever gotten from his own mother: "She said, '[the] best way to get happy is make somebody else laugh, and that will make you happy.' And she was right. I've been doing it a lot of years."

Marshall is survived by his wife, Barbara Marshall, two sisters, Ronny Hallin and Penny Marshall, and three children, Kathleen, Scott and Lori. His family is planning a private funeral and a memorial service to be held on his birthday on Nov. 13.

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