As Olivia Newton-John continues to battle cancer, the 69-year-old singer of such hits as “Physical” and “Magic” revealed during a new TV interview that her current fight with the disease is actually her third, having kept an earlier diagnosis a secret.

Speaking with Australia’s “Sunday NIght”, the “Grease” star explained why she didn’t go public with that diagnosis after candidly discussing her first cancer battle two decades earlier. “I thought, ‘It’s my life’ and I just decided to keep it to myself.”

In 2013, the Australian-born singer and actress revealed, she was involved in a minor car accident that led to the discovery a lump on her back. After initially thinking it was caused by the strain of the seat belt, subsequent scans revealed the lump was actually a return of the breast cancer she had beaten in her earlier health scare.

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After her cancer had gone into remission for the second time, Newton-John told “Sunday Night” that she was later diagnosed with a tumour at the base of her spine, a battle that she’s still waging.

She’s undergone radiation therapy, and is also embracing natural remedies — including medical marijuana that her husband of 10 years, John Easterling, grows at the couple’s ranch in Santa Barbara, California.

“In California, it’s legal to grow a certain amount of plants for your own medicinal purposes… I’m very lucky that I live in a state where it’s legal and that I have a husband that is a plant-medicine man,” she explained.

RELATED: Olivia Newton-John Says Smoking Pot Helped Her Battle Against Cancer

Despite her continual health issues, Newton-John refuses to be consumed by negativity. “There are other people out there doing much, much worse than me. I’m a very privileged person, and I’m very aware of that,” she added. “I live in this beautiful place. I have a wonderful husband. I have all the animals that I adore. I have an incredible career. I have nothing, really, to complain about.”

Asked about whether she was worried, Newton-John radiated optimism. “I believe I will win over it, and that’s my goal.”

You can watch the interview in its entirety above.

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