The "Grease" star posted a throwback photo on Instagram on Oct. 13 showing the couple embracing one another. "Happy birthday to my favorite dance partner! We love you and miss you Kelly," he captioned it.

Travolta and Preston's daughter, Ella, 22, responded by adding three red heart emoji in the comments.

Preston died of breast cancer in 2020 at age 57. She and Travolta also shared two sons, Benjamin, 11, and Jett, who died in 2009 at the age of 16.

In May, Travolta paid tribute to the late "Jerry Maguire" star on Mother's Day. Next to a video montage of family photos that he set to Barbra Streisand’s song “That Face," he wrote, "We love and miss you Kelly. Happy Mother’s Day."

Travolta has previously opened up about the grief he's suffered with since Preston's death.

“Mourning is individual and experiencing your own journey is what can lead to healing,” he told Esquire Spain in 2021. “The most important thing you can do to help another when they are in mourning is to allow them to live it and not complicate it with yours.”

“The first thing you should do when you experience grief is to go to a place where you can mourn, without any interference,” he added. “If I die tomorrow, the last thing I want to see is that everyone around is sunk.”

During an appearance on Kevin Hart’s Peacock series, “Hart to Heart,” last year, the "Pulp Fiction" star revealed how he has spoken about death to his son Ben.

“‘Nobody knows when they’re going to go, when they’re going to stay,'" he recalled telling his son.

“‘Your brother left at 16, too young. Your mother left at 57, that was too young, but who’s to say? I could die tomorrow. You could. Anybody can. It’s part of life. You don’t know exactly. You just do your best at trying to live the longest you can.'"