A post-mortem examination determined last night that John Travolta’s chronically ill son died of a seizure, as controversy erupted over the Scientologist actor’s handling of the boy’s medical condition.

According to the family, Jett, 16, suffered a seizure and hit his head on a bathtub at their holiday home in the Bahamas, where he was found dead on Friday.

Glenn Campbell, the assistant director of a local funeral home, said that the body was in “great condition” with no sign of head trauma. He said that the death certificate, based on the post-mortem examination, gave the cause of death as “seizure”.

Jett’s remains were expected to be flown from Grand Bahama to the family home in Ocala, Florida, today. Travolta and his wife, Kelly Preston, issued a statement saying they were “heartbroken that our time with him was so brief. We will cherish the time we had with him for the rest of our lives.” The couple said that Jett suffered from Kawasaki disease, a condition that causes inflammation of small and medium-sized arteries. The disease affects the lymph nodes, skin and the mucous membranes in the mouth, nose and throat.

Experts said that the disease was rarely fatal and seldom affected children over the age of 8. The Travoltas have linked their son’s condition to house-cleaning agents. “With my son I was obsessive about cleaning — his space being clean, so we constantly had the carpets cleaned,” Travolta told CNN in 2001. “And I think, between him, the fumes and walking around, maybe picking up pieces or something, he got what is rarely a thing to deal with, but it’s Kawasaki syndrome.”

Preston said in 2003 that she had detoxed her son in a programme devised by L. Ron Hubbard, the founder of Scientology. “I had a friend of mine, an environmental scientist and a toxicologist, go through our home and tell us exactly what was going on in the home. It wasn’t only the carpet. We had lots of cleansers under the sink.”

Critics of Scientology suggested yesterday that Jett may have been suffering from autism, a condition that the church does not recognise because it considers mental illness to be psychosomatic and argues that it should be treated through spiritual healing.

Joey Travolta, the star’s film-maker younger brother and an autism activist, reportedly clashed with his brother about what was wrong with Jett. Joey Travolta worked on a documentary called Normal People Scare Me and helped to found Actors with Autism.

Paul Bloch, Travolta’s spokesman, did not respond to a request for a comment. His lawyers rejected suggestions that the star, who tried to revive his son with CPR, did not care properly for Jett. Michael McDermott and Michael Ossie, who represent the star, told the website TMZ.com that Jett suffered frequent seizures and that “each was like a death”, with the boy losing consciousness and convulsing.

Jett took the anti-seizure drug Depakote for several years, reducing the frequency of his seizures from an average of every four days to once every three weeks, they said, but the drug lost its effectiveness. The Travoltas, after consulting neurosurgeons, stopped administering it and Jett went back to having one seizure a week.

John Travolta

Born February 18, 1954, in Englewood, New Jersey. His father owned a tyre repair shop

Shot to fame in Grease, the 1978 film co-starring Olivia Newton-John

Nominated for two Oscars as Best Actor in a Leading Role: Pulp Fiction (1994) and Saturday Night Fever (1977)

Lent his voice to the lead character - a dog - in Bolt, the latest Disney animation, out next month

Married to the actress Kelly Preston since 1991. Jett was born in 1992. Their daughter, Ella Bleu, was born in 2000

The actor enjoys flying and has his own Boeing 707-138

He became a Scientologist in 1975

Sources:www.travolta.com ; www.imdb.com

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