John Travolta honors Olivia Newton-John: 'My dearest Olivia'

John Travolta, Richard Marx, and other celebrities paid tribute to "Grease" star Olivia Newton-John after her death was announced Monday.

"My dearest Olivia, you made all of our lives so much better," Travolta wrote on Instagram alongside a photo of the actress. "Your impact was incredible. I love you so much. We will see you down the road and we will all be together again. Yours from the moment I saw you and forever! Your Danny, your John!"

Newton-John's death was announced on her social media. The actress had been diagnosed with stage four metastatic breast cancer in 2017.

"Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer," the statement read.

"Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer. In lieu of flowers, the family asks that any donations be made in her memory to the @onjfoundation."

Other celebrities took to social media to pay tribute to the actress.

"My sweet friend--I will miss you forever," Patrick McDermott's ex-wife Yvette Nipar wrote on Twitter.

McDermott and Newton-John had dated before the Hollywood cameraman and lighting technician went missing. Newton-John and Nipar reportedly became close throughout the years following the disappearance.

Musician Richard Marx wrote: "My heart is broken. Rest now, sweet friend. You were as kind and loving a person as there’s ever been. I’ll miss you every day."

Barbra Streisand shared a photo of herself with the actress.

"Too young to leave this world. May she RIP," she captioned the photo.

George Takei wrote, "We have lost a great, iconic artist in Olivia Newton John, gone too soon from us at age 73. I trust she is now in the great Xanadu beyond. Know that we are forever hopelessly devoted to you, Olivia. Rest in song and mirth."

Musician Michael Des Barres shared his own tribute on Twitter.

"Olivia Newton-John had the extraordinary gift of while she sang and acted she became your sister," he wrote. "A member of your family. The Sweet brilliance she sent out into this fearful world was rar & beautiful."

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FILE - Singer Olivia Newton-John performing in a BBC television studio, circa 1971. (Warwick Bedford/Radio Times via Getty Images)

Newton-John had an accomplished career as a musician, actress, entrepreneur, and activist. The "Physical" singer won four Grammys throughout her career and earned 12 nominations.

She was known for her hits "I Honestly Love You," "Hopelessly Devoted to You," and "Twist of Fate."

On top of her music, Newton-John gained fame for her role as Sandy in "Grease." The film was released in 1978.

Other movies she was known for include "Xanadu" and "Two of a Kind."

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