John Travolta has paid tribute to his late son Jett on what would have been his 28th birthday.

The 'Grease' star and his wife Kelly Preston have publicly remembered their late son, who passed away in 2009 during a family trip to the Bahamas, when he hit his head on a bathtub after suffering a seizure at their home on Grand Bahama Island.

In a post on Instagram that featured a black and white photo of himself and Jett, the 66-year-old actor wrote: ''Happy Birthday Jetty! We love you! (sic)''

Following his post, several stars left comments showing their support, including Queen Latifa - who left a series of praying and heart emojis - and musician Tommy Lee, who commented with a purple heart emoji.

Olivia Newton John - who starred alongside John in 'Grease' - also left a comment, which consisted of a praying emoji, a red heart, and a rainbow.

John's wife Kelly shared her own image of herself giving Jett a hug.

She wrote alongside it: ''Happy Birthday to our sweetest Jetty, we love you!! (sic)''

Both John and Kelly - who married in 1991 - tagged each other in their posts, as well as their 20-year-old daughter Ella, who shared her own post remembering her big brother.

She posted: ''Happy Birthday to my brother Jett, I love you so much (sic)''

The couple are also parents to nine-year-old son Benjamin, who was born just over a year after Jett's tragic passing.

John has previously credited Benjamin with helping to ''re-bond'' the family after the ''tremendous loss'' they suffered following Jett's death.

The 'Pulp Fiction' star said in 2016: ''We certainly have bonded together. Certainly, having little Ben has been a beautiful kind of glue for us to re-bond after a tremendous loss.''