Olivia Newton-John and Arnold Schwarzenegger were among the stars to pay tribute to John Travolta's wife Kelly Preston, who passed away on Sunday following a two-year battle with cancer.
READ: John Travolta breaks silence following death of wife Kelly Preston
Arnold, who starred alongside the late star in Hollywood movie Twins, expressed his sadness over the tragic news, tweeting: "Kelly Preston was extraordinary. I was lucky enough to star with her and direct her, and her talent was off the charts. She had such a big heart, she was a wonderful wife and mother, and my thoughts are with John and the whole family."
WATCH: Kelly Preston dies aged 57
Kelly is survived by her actor husband and their two children - Ella, 20, and nine-year-old son Benjamin. Tragically, their son Jett died aged 16 in January 2009.
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John's Grease co-star Olivia – who has also battled cancer three times – touched upon Kelly's "gentle spirit" in a heartfelt message posted to Instagram. "@therealkellypreston was a radiant, warm and gentle spirit - a loving, devoted wife, mother and sweet friend," she wrote alongside a throwback snap of the pair.
"My heart breaks for John, Ella and Ben. No words can express my sorrow for her family. Kelly’s light shines on in her beautiful children. Xox." John and Olivia have remained the best of friends ever since playing love interests Danny Zuko and Sandy Olsson in iconic classic Grease.
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In another post, Olivia shared the CHEC 'Not Under My Roof' initiative that the pair had worked on to protect children's health. "I was proud to launch the CHEC 'Not Under My Roof' initiative with @therealkellypreston 20 years ago," she said. "She was passionate about safety for children from environmental toxins, and we made this video for the Children’s Health Environmental Coalition (CHEC) which is now HealthyChild.org.
John Travolta and Olivia Newton-John starred together in Grease
"Thanks to Kelly’s passion to protect children's health - from her own personal experience - she helped catapult the children’s environmental health campaign."
Kelly starred in a number of films throughout her film career, including Space Camp, What A Girl Wants, Twins and For The Love Of The Game. Her last movie role was in the 2018 film Gotti, in which she appeared as Victoria Gotti, the wife of Mafia boss John Gotti, who was portrayed on screen by her husband.