'Grease' star Olivia Newton-John dies aged 73

Oh, Sandy! Olivia Newton-John broke hearts worldwide when she starred opposite John Travolta in "Grease"

Singer Olivia Newton-John, who gained worldwide fame as high school sweetheart Sandy in the hit musical movie "Grease," died on Monday after a 30-year battle with cancer. She was 73.

Newton-John "passed away peacefully at her ranch in Southern California this morning, surrounded by family and friends," said a statement from her husband John Easterling posted on her official social media accounts.

The British-born and Australian-raised star dedicated a number of albums and concerts to raise funds for research and early detection of the disease, including the construction of a health center named after her in her adopted home Melbourne. 

"I like to say 'win over,' because 'battled' sets up this anger and inflammation that you don't want."

- 'Sandy and Danny' -

The high school sweetheart-turned-bad girl resonated with audiences worldwide, and continues to capture hearts decades after the movie was released. 

"It is incredible that it is still going but it's not even just that, it's showing no signs of stopping. You say 'Sandy and Danny' and people instantly know what you're talking about."

"My dearest Olivia, you made all of our lives so much better. Your impact was incredible. I love you so much," wrote Travolta, in an Instagram post Monday signed "Your Danny, your John!"

There was no one else "in the universe" who could play Sandy, he said of Newton-John, who turned 29 during the making of Grease and later revealed she had to be convinced by Travolta to take up the role after self-doubts that she was too old to play a teenager. 

"Every boy's, every man's dream was: 'Oh I would love for that girl to be my girlfriend'."

"She was, and always will be, an inspiration to me in so many, many ways," the singer wrote on Twitter.

Born in Cambridge, England in 1948, Newton-John was the youngest of three children. 

A passion for music saw her perform in several Australian TV shows as a teenager, before moving to England in the 1960s where she teamed up with fellow Australian performer Pat Carroll on the UK pub and club circuit.

The 1981 hit song "Physical," which saw Newton-John don a headband and spandex amid an 80s fitness culture boom, demonstrated the dexterity of a performer able to reinvent herself amid cultural change.

Her philanthropy and passion for cancer research came to the forefront, championing natural therapies including medicinal cannabis in the treatment of cancer.

"So I feel grateful for anything that happens now."

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