John Travolta remembers Olivia Newton-John

Fans, peers and co-stars are honoring “Grease” lead Olivia Newton-John shortly after her death was announced Monday. The singer-actor died at 73 at her ranch in Southern California. Although a cause of death wasn’t revealed, Newton-John had fought breast cancer for 30 years.

Among those paying tribute on social media was John Travolta, who said his “Grease” co-star — who played Sandy to his Danny in the 1978 musical comedy — “made all of our lives so much better.”

“Your impact was incredible. I love you so much. We will see you down the road and we will all be together again. Yours from the first moment I saw you and forever! Your Danny, your John!,” he wrote in an Instagram post.

Also honoring the late singer were actor Daniel Dae Kim and filmmaker James Gunn, who remembered Newton-John as their first crush.

“Really sad to hear about the passing of Olivia Newton-John. My first real crush as a kid. I loved Grease & her music & I coincidentally also bought & lived in a for a while the wonderful home she built in Malibu. May she Rest In Peace,” Gunn tweeted.

Comedian Dane Cook thanked Newton-John for “wonderful music and fun memories.” Also sharing their praise for the “hitmaker were George Takei, Marlee Matlin and Gabrielle Union, among others.

“”Grease” is my #1 movie of all time and made me a lifelong Olivia Newton John fan,” tweeted Union. “Me and my sister watched Xanadu more times than I could count. Sending so much love and prayers to a real gift of a woman and talent.”