Olivia Newton-John shared a final post on Instagram just days before she died at the age of 73.
Her husband John Easterling confirmed her death on Instagram, saying she died peacefully at her ranch in the US state of California on Monday (local time).
Olivia had battled breast cancer for the past 30 years, with the family asking for donations to be made in her memory to the Olivia Newton-John Foundation in lieu of flowers.
In her final days, Olivia posted a throwback photo on Instagram of her cuddling up with her husband John, who she married in 2008.
She captioned the photo "#flashbackfriday", and hundreds left comments about how beautiful the love between the pair was.
"So beautiful," singer Delta Goodrem said.
"My favourite couple," another wrote.
"There is nothing more beautiful than seeing you smile and enjoy nature, in the company of your beloved," a third added.
In the post confirming her death, John said Olivia had been a symbol of triumphs and hope.
"Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer," he wrote.
Olivia and John met in the early 90s but didn't start dating until she was 59 after her ex-partner Patrick McDermott went missing while on a boating trip in 2005.
After marrying John in 2008, Olivia told PEOPLE in an interview she had been dating at the time but didn't expect to fall in love with him.
John Travolta's touching tribute to Olivia
A number of celebrities have shared touching tributes in the wake of the news of Olivia's death, with Grease star John Travolta, who famously played her love interest Danny Zuko, posting a heartfelt message on Instagram.
"You made all of our lives so much better. Your impact was incredible. I love you so much," he wrote.
"We will see you down the road and we will all be together again. Yours from the first moment I saw you and forever! Your Danny, your John!"
Just days before Olivia's death, her daughter Chloe Lattanzi took to Instagram to share a photo of them together with the caption, "I worship this woman. My mother. My best friend. @therealonj."
Hours after her mother's passing was announced, Chloe shared a series of photos of the two of them together over the course of her life.
The first photo featured a young Chloe kissing her mum during a photoshoot, with the second showing Olivia holding Chloe as a baby. Other photos she shared were more recent.
Never miss a thing. Sign up to Yahoo Lifestyle’s daily newsletter.
Or if you have a story idea, email us at email@example.com.