Olivia Newton-John sent a letter to Delta Goodrem when she was diagnosed with cancer.

Delta Goodrem

Delta Goodrem

The 34-year-old singer and actress plays the 'Grease' star in the new Lifetime biopic 'Olivia Newton-John: Hopelessly Devoted to You', but first met the 70-year-old star as a child when she spent a lot of time hanging around backstage at various events.

And when Delta was diagnosed with Hodgkin's lymphoma in 2003 at the age of 18, she was surprised to receive a "beautiful letter" from Olivia, who had been diagnosed with breast cancer several years earlier in 1992.

Delta said: "She sent me a letter when I got diagnosed with cancer and she said beautiful words and told me that, 'One day, you'll see this is a gift and understand to give back and let people know you can be a tower of strength.' So that was my next beautiful letter from her. Then we ended up writing songs together for her album and for her charity [so] that was the start of our friendship."

The 'Born To Try' hitmaker even got a call from Sir Elton John on her first day of chemotherapy, who told her the whole of Britain hoped she got "better".

She added: "I went from planes, trains and automobiles to my whole world [being] haematologists and oncologists. I began the fight. That's life. I was surrounded by beautiful family and the whole country and we had special moments - I'll never forget Elton John calling me on my first day of chemotherapy and saying, 'On behalf of Britain, we hope you feel better.' It was a pretty extraordinary time."

Olivia, meanwhile, has since been diagnosed with breast cancer a further two times and is currently on the road to recovery following her third diagnosis, which Delta believes is "incredible".

Speaking to People magazine, she said: "The fact that she's, right now, on the road to recovery and she's staying on schedule and she's coming back with a book tour in March is incredible. She's so positive and stands there as a warrior. That's what I think you learn in the biopic, you realise that through everything that happens to her, she wants to make sure that other people remember to fight. There's a reason for everybody knowing about what she goes through in music or anything so that she can bring good and make a difference in the world."

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