Jett died in 2009 following an accident while the family was vacationing in the Bahamas. He was 16.
In the post, John shared a sweet black-and-white shot of him smiling at Jett, while the younger Travolta grinned for the camera.
“Happy birthday my beautiful Jetty,” John wrote. “I love you.”
John and Kelly’s 21-year-old daughter, Ella, commented on her dad’s post with three red heart emojis.
John’s birthday tribute to Jett came just less than a year after Kelly’s death following a cancer battle. She was 57. Last year, prior to Kelly’s death, both she and John posted birthday tributes to Jett.
At the time, John shared a similar shot of himself with Jett as he did this year, while Kelly posted a pic of her and her son sharing a hug.
“Happy Birthday Jetty! We love you!” John wrote, with Kelly adding, “Happy Birthday to our sweetest Jetty, we love you!!”
Watch the video below for more on Travolta and Preston’s family.
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