On Wednesday, during an interview on Today, host Kotb, 57, talked to the 73-year-old singer about remaining optimistic throughout the years despite the obstacles she's faced. Newton-John was diagnosed with stage 4 metastatic breast cancer in 2017, nearly 30 years after her first diagnosis.
Kotb opened up about her own experience with cancer, comparing herself to Newton-John and her ability to stay positive. The beloved Grease star was shocked to learn that Kotb herself had been treated for breast cancer 14 years ago.
"I'm really sorry you went through that," Newton-John told Kotb, who held back tears in the interview. "I didn't know that about you. So you're well now, you're doing good?"
— TODAY (@TODAYshow) October 20, 2021
"Yes, I'm doing good," Kotb assured. "By the way, I'm just going to pause for a second. Another wonderful thing about you is what you just did there. Thank you. Thank you for asking."
Newton-John then quickly responded, "Oh, of course. We're sisters. Anyone that has gone on this journey with cancer, it's unknown destinations and surprises and turns."
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Newton-John was first diagnosed in 1992 and overcame cancer again in 2013. In May 2017, she was told the cancer had metastasized and spread to her bones. However, the actress told reporters last year at G'Day USA in Beverly Hills, California, that she doesn't see it "as a battle."
"I'm winning over it well and that's how I see it," she said. "I don't think about it a lot, to be honest. Denial is a really good thing and I'm getting stronger and better all the time! I'm doing well!"
In February, Newton-John told PEOPLE that she had been "feeling great" — so much so that she and her husband, John Easterling, launched their Olivia Newton-John Foundation Fund in order to continue to support research into plant medicine for cancer.
During Wednesday's interview, the singer explained that right now, she's "feeling pretty good," managing her pain with medical marijuana with the help of Easterling.
"I have my days, I have my pains, but the cannabis that my husband grows for me has been such a huge part of my healing, and so I'm a really lucky person," she told Kotb.