Entertainment Movies John Travolta Posts Heartfelt Message to Late Olivia Newton-John on Her 74th Birthday: 'My Olivia' John Travolta is still honoring his late Grease co-star Olivia Newton-John on what would've been her 74th birthday, after she died in August By Tommy McArdle Tommy McArdle Tommy McArdle is an editorial assistant on the Movies team at PEOPLE. Tommy joined PEOPLE in 2022. People Editorial Guidelines Published on September 27, 2022 08:28AM EDT John Travolta couldn't forget Olivia Newton-John on what would have been her 74th birthday. On Monday night, Travolta, 68, shared a still image on his Instagram Story of himself and Newton-John, who died in August after a years-long fight against breast cancer, from their time starring in the hit 1978 movie Grease. "Happy birthday my Olivia," Travolta wrote in a caption written underneath the photo of the pair as their iconic Grease characters Danny Zuko and Sandy Olsson in their end-of-movie all-black costumes. Travolta was not the only person close to Newton-John celebrating her birthday less than two months after her death. Chloe Lattanzi, Newton-John's daughter, shared a video of herself and other family members "celebrating my beautiful mom's birthday" Monday on Instagram as well. Newton-John's widower, John Easterling, can also be seen in the video and in a separate clip Lattanzi shared to her own Instagram Story, of several family members celebrating at dinner. Never miss a story — sign up for PEOPLE's free daily newsletter to stay up to date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. John Travolta's Instagram Story. PARAMOUNT PICTURES/Album; John Travolta Instagram John Easterling Recalls One of His First Vacations with Olivia Newton-John on Late Wife's Birthday Travolta and Newton-John shared a friendship that spanned decades past their involvement in Grease. The pair even reunited and dressed up as the iconic lovebirds during the Meet n' Grease sing-along event at the Coral Sky Amphitheater in West Palm Beach, Florida, back in December 2019. "We did something life-changing, making that film," Newton-John told PEOPLE back in 2018 on the film's 40th anniversary. She continued, "[At the premiere] you got the feeling from the energy that something was happening. It was a huge response. I feel grateful to be a part of that and to have worked with him. We've stayed friends ever since." "[In tough times] John always reaches out to me," Newton-John added, as Travolta said, "When you share that kind of meteoric success — and nothing has been able to exceed it — you share a bond." New PEOPLE Special Edition: Olivia Newton-John on Why She Initially Turned Down Grease "I've been through her having a child, getting divorced, losing her sister. She's been through my getting married, having children. It's wonderful and full of shared memories," the actor added. Travolta previously posted a loving tribute to Newton-John on Instagram after her death in August, noting his former costar's "incredible" impact. "My dearest Olivia, you made all of our lives so much better," he captioned a throwback photo of Newton-John. "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 moment I saw you and forever! Your Danny, your John!" Travolta concluded.