John Travolta is sending a loving message to his late son Jett Travolta.

The Grease alum shared a post on Instagram for his and his late wife Kelly Preston‘s son on what would’ve been his 33rd birthday.

“Happy birthday Jett – I miss you so much,” John wrote April 13 alongside a throwback photo of the father-son duo. “Love you forever!”

Although Jett died at age 16 in 2009 after having a seizure while on vacation with their family, the Oscar winner and Kelly—who also share kids Ella Bleau Travolta, 24, and Benjamin Travolta, 14—paid tribute to their eldest son each year. 

Sharing a photo of himself with Kelly—who died in 2020 at age 57 following a two-year battle with breast cancer—and Jett, John wrote on Instagram last April, “Not a day goes by where you’re not with me!”

Meanwhile, among the Battlefield Earth actress’ final social media posts was also a birthday message for Jett. But she also took some time to share insight into their son’s autism diagnosis just one week earlier to honor National Autism Acceptance Month.