Jett died in 2009 from a seizure at the age of 16 on a family vacation in the Bahamas.
“My dearest Jetty, I miss you more than words can say,” the Oscar-nominated star wrote on his Instagram post of an old black-and-white photo of the two. “I think about you everyday. Happy Birthday. Love, your Dad.”
Jett was Travolta’s firstborn with late wife, Kelly Preston, who died in July 2020 after a long battle with breast cancer.
Travolta and Preston married in 1991 and had three children: Jett, Ella and Benjamin.
Travolta has never shied away from discussing the impact his wife and son’s deaths had on his family.
He shared the conversation he had with his son Ben, now 11, following Preston’s death: “Your brother (Jett) 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,” Travolta told his son. “So let’s look at it like it’s part of life. You don’t know exactly. You just do your best at trying to live the longest you can.”
Fans, friends and family members of the “Pulp Fiction” star shared loving messages in the comments, including Travolta’s daughter, Ella, who wrote, “Happy Birthday Jetty, we love you so much.”
Actress Jamie Lee Curtis, who co-starred in the film “Perfect” alongside Travolta, commented: “Oh John. My hand in yours. X j.”
Travolta and Ben recently adopted Mac N Cheese, the rescue dog Curtis had brought onstage during a tribute to Betty White at the Oscars.
“Nothing worse than losing a child. I feel your pain. So sorry,” another fan commented.
Travolta and his wife kept Jett’s legacy alive over the years on social media, including on World Autism Awareness Day in 2019 when Preston shared a photo of Jett, who is autistic.
“To my sweet love, Jett... you are in our hearts forever. I send love to all of the beautiful autistic children and the wonderful people who love them,” she wrote.