In an exclusive interview with Closer Weekly, on newsstands now, Olivia Newton-John opens up about how she overcame the tragedy of her sister's death through music.

“I lost my sister Rona Newton-John to a rare form of brain cancer three years ago,” Olivia, 68, shares with Closer. “I was in a lot of grief, so I wrote a song to express my feelings.”

Now the star has channeled her pain into a new CD, LIV ON. “When I’ve gone through great emotional upheaval, I’ve always used music to heal myself,” the Grease star reveals. “I hope it helps other people, too.”

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Olivia and Rona in 2004.

“After my friend Amy Sky helped me finish a song about my sister, we talked about the fact that there isn’t a lot of music about grief,” Olivia tells Closer.

MORE: New Details Emerge About Olivia Newton-John's Missing Ex-Boyfriend — Get the Latest!

“I came up with the concept for an album about loss, hope and moving forward,” she explains. “It’s important for people to know that it’s all right to cry. We all go through loss. It’s part of life’s journey.”

For the full interview with Olivia Newton-John, pick up the latest issue of Closer Weekly, on newsstands now!

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