John Travolta and Kelly Preston pay tribute to late son Jett on what would have been his 28th birthday

John Travolta and Kelly Preston won’t ever forget their “Jetty.”

They shared sweet messages on Monday of their late son, Jett Travolta, who would have turned 28 this week.

“Happy Birthday Jetty! We love you!” the “Grease” actor, 66, wrote alongside a photo of them together.

“Happy Birthday to our sweetest Jetty, we love you!!” the “Jerry Maguire” actress, 57, said with a photo of them hugging.

Jett, who had autism, died in January 2009 at the age of 16 after suffering a seizure while on vacation with his family in the Bahamas.

Ella Travolta also shared a tribute to Jett. “Happy Birthday to my brother Jett, I love you so much,” the 20-year-old captioned a family photo.

In addition to Ella, the longtime couple are also parents to 9-year-old Benjamin.