Olivia Newton-John, beloved as Sandy in 'Grease,' dies at 73 after breast cancer battle

Olivia Newton-John, the Grammy Award-winning singer and actress best known as the goody two-shoes Sandy in "Grease," has died at age 73 following her battle with breast cancer.

Newton-John's husband, John Easterling, confirmed his wife's death Monday via her verified Facebook page, writing that Newton-John "passed away peacefully at her ranch in Southern California this morning, surrounded by family and friends."

"Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer," Easterling wrote. "Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer."

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A pop singer-turned-icon following her starring role in the hit movie musical, Newton-John was also a fierce advocate of cancer awareness.

She battled a third round of cancer in 2017, this time at the base of her spine. An initial breast cancer diagnosis came in 1992; doctors again found cancer, in Newton-John's shoulder, following a car accident in 2013.

When asked in a September 2018 interview with Australia's Channel Seven whether she was scared following the third diagnosis, she said, "I'd be lying if I said I never go there. There are moments; I'm human. If I allowed myself to go there, I could easily create that big fear. But my husband's always there, and he's there to support me.

"I believe I will win over it. That's my goal."

Newton-John was born Sept. 26, 1948, in Cambridge, England, and moved with her family to Australia at age 5. She grew up singing and won a talent show at 16 that sent her to England, after which she dropped out of high school to pursue performing full-time.

Her first major success as a pop star came with a cover of Bob Dylan's "If Not For You" in 1971, which hit No. 25 on Billboard's Hot 100 chart and catapulted Newton-John to international stardom.

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Possessing a honeyed voice ideally suited to innocuous midtempo songs, Newton-John commandeered both pop and country radio in the mid-'70s with hits "Let Me Be There," "If You Love Me (Let Me Know)," "Have You Never Been Mellow" and the whispery ballad that would become one of her trademarks, "I Honestly Love You."

Her star-making turn with John Travolta in "Grease" was heightened by the film's massively successful soundtrack, which was the second-best-selling album of 1978 and has been certified more than 8 times platinum.

"Hopelessly Devoted to You" – which received an Oscar nomination for best original song in 1979 – as well as her duets with Travolta, "You're the One That I Want" and "Summer Nights," have become multigenerational favorites and, at the time, provided Newton-John with an entry into pop stardom.

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Her 1980s output included two hits from the much-maligned film "Xanadu" – the title track with Electric Light Orchestra and "Magic" – before Newton-John struck MTV infamy in 1981 with "Physical."

The frothy pop tune – a winking nod to sex – signified a shift in Newton-John's previously wholesome persona, while the video featuring the singer in a tight leotard raised eyebrows in its day.

During a 2017 concert in Atlanta, Newton-John joked that compared to current radio selections, "Physical" is "more like a lullaby!"

But the bouncy tune – which Billboard ranked No. 1 on its Top 100 Songs of the 1980s list – also prompted a parade of additional hits for Newton-John throughout the decade, including "Twist of Fate," "Make a Move on Me" and, in 1986, "The Best of Me" with super-producer David Foster.

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Newton-John relocated from England to the U.S. in 1975 at age 27. Three years later, she starred alongside Travolta in the cult-classic film adaptation of the stage musical "Grease," which earned her a Golden Globe nomination for best actress in a musical.

She married Matt Lattanzi in December 1984 and their daughter, Chloe Rose Lattanzi, was born a little more than a year later. The couple divorced in 1995 and Newton-John soon began dating cameraman Patrick McDermott, who disappeared during a fishing trip off San Pedro, California, in 2005. The Coast Guard concluded he most likely drowned.

Newton-John and producer John Easterling wed in 2008.

Her sister, Rona Newton-John, an actress in the 1960s and '70s, died of from brain cancer in May 2013 at age 70. She was married to Jeff Conaway, best known as Kenickie in "Grease," from 1980 to 1985. Conaway died in 2011.

"My beautiful sister Rona sadly passed on May 24th in Los Angeles," Olivia wrote in a Facebook post. "It was May 25th in Australia – which was our mother Irene's birthday. Rona died of a very aggressive brain tumor and mercifully suffered no pain. ... I will miss her forever – my beautiful, smart, talented, funny, brave sister Rona."

After losing her sister and battling a diagnosis herself, Newton-John became known for her advocacy to fight cancer. One project, a collaboration with Beth Nielsen Chapman and Amy Sky on the 2016 album "Liv On," sought to express grief and dealing with loss with inspiring messages of hope and healing.

“Going through loss and illness and everything is part of life, everybody’s, no one escapes it,” Newton-John told the Asbury Park Press, part of the USA TODAY Network, in 2017. “So it was important to me to include that. … I try to give positive messages. 'Liv On' is a positive song, 'Not Going to Give Into It' is a positive song and it shows that you can go through difficult things and live on with joy and I’m very grateful for that."

She also performed in a three-year residency in Las Vegas starting in 2014, from which a portion of ticket proceeds went toward the Olivia Newton-John Cancer Wellness and Research Centre in Melbourne, Australia.

“I wasn’t sure whether I wanted to get behind having a building with my name on it. It was all very overwhelming,” Newton-John told the Asbury Park Press. “And I asked my mother and she said, ‘Listen, darling, if you can help somebody, then you should do it.’ That was just the most important, basic and obvious answer. So if it’s something that touches my heart and I feel like I can help, then I’ll do it.”

Newton-John is survived by her husband Easterling, daughter Chloe Lattanzi, sister Sarah Newton-John, brother Toby Newton-John and numerous nieces and nephews.

In lieu of flowers, the family asks that donations be made in her memory to the Olivia Newton-John Foundation Fund.

Contributing: Edward Segarra, USA TODAY

This article originally appeared on USA TODAY: Olivia Newton-John dead: 'Grease' star dies at 73 after cancer battle