Olivia Newton-John: Australia mourns a national sweetheart

Olivia Newton-John was a UK-born, Australian-raised recording artist who shot to superstardom in the US.

It's no wonder that Hollywood is mourning her and that tributes have come from her star friends from Britain as well.

But Australia has and will always claim her as its "darling" and "sweetheart".

This is where she started her musical career, even though she grew up wanting to be a vet and then a policewoman.

Newton-John formed a girl group with three other school friends at 14 and started performing in a café run by her sister's boyfriend.

Australians grew up with a young Olivia Newton-John on their screens.

She appeared on many talent shows. She sang Summertime aged 15 on a televised talent competition and landed a role on the TV programme The Happy Show.

On Sing Sing Sing, another talent show in Sydney, she won top prize: a trip to England.

Even after she was catapulted to major Hollywood fame, starring opposite John Travolta as Sandy in Grease, Australia was proud of their "girl who made it".

Australians are reminiscing over many memorable moments. One of them, of course, is when she sang for the Queen at the Sydney Opera House in 1980. She also performed at the Sydney Olympics in 2000.

This morning, as the country woke up to the news of her death, her name has dominated Australian social media and news programming.

Even when they went to other news of the day, Australia's national broadcaster ABC had one ongoing ticker on the screen: "Olivia Newton-John dies - Tributes flood in following death of the Australian star".

"For all of us who grew up watching Grease, an era has ended," said Australia's Deputy Prime Minister Richard Marles.

Former Foreign Minister Julie Bishop said Newton-John had remained "relatable and loveable" despite global superstardom.

"Everybody wanted to be her friend. And I remember as a teenager at school when the first song or first big hit - If Not For You - came out, every girl wanted to be Olivia," she said.

Tributes have also poured in from other Australian stars, including Kylie Minogue, Hugh Jackman and Delta Goodrem.

Her songs are etched in the memories of millions. Many fans have said they'll be listening to hits like You're The One that I Want and Physical in remembrance.

The star was also known for her philanthropy. She was diagnosed with breast cancer in 1992, the same year her father died of cancer.

For decades she has raised awareness and significant funds for cancer research.

She called on Australia to follow California - where she lived with her family - to legalise medicinal marijuana.

"My dream is that in Australia soon, it will be available to all cancer patients and people going through cancer that causes pain," she said.

Today, flags are flying at half-mast outside the Olivia Newton-John Cancer Wellness and Research Institute in her hometown of Melbourne.

The institute was "her dream and… her legacy", said fundraising director Debbie Shiell on Tuesday.

"She drove around the corner and saw her name up on the building. She said it was better than any billboard she's ever seen," a visibly emotional Ms Shiell told ABC News, adding she was "a beautiful soul".

"She gave so much hope to so many people.

"Olivia would sign off a lot of her emails: 'Love and light, Olivia.' And she was love and light."

Many cancer patients and survivors have sent their tributes to the ABC as well.

"Olivia was a large part of the sound track of my life," said Robyn. "Her courage facing breast cancer supported me when I faced it myself. Vale Olivia, we were fortunate to have you."

Rosie, a patient at Newton-John's institute in Melbourne, wrote of her "deep gratitude for all Olivia did to raise awareness and provide practical, sensitive support for those going through breast cancer".

"Her investment into that facility and research is a wonderful legacy," she said.

Olivia Newton-John will no doubt be remembered as a musical icon. But as Australia bids farewell to its "sweetheart", she will also be remembered as a symbol of kindness and hope.