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Since the January death of John Travolta's 16-year-old son, Jett, he has remained out of the public eye. On the rare occasions when the actor has been spotted, he's been on his own -- jetting to Miami for a quiet lunch or flying to Tahiti to seek solitude on what would have been Jett's 17th birthday. But it seems his dignified silence during his grieving process has only served to crank up the rumor mill.

"Is John Travolta cracking up?" the London Daily Mail insensitively asks. "It's not just grief -- and guilt -- over his dead son that are tearing the actor apart."

The paper alleges that the star remains in "a state of almost constant distress," which it believes is "compounded by the first cracks in his 34-year relationship with the Church of Scientology."

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Travolta, who is also dad to 9-year-old Ella Bleu with wife Kelly Preston, has purportedly had his belief system "deeply shaken" in the wake of Jett's passing from a reported seizure disorder while the family was vacationing in the Bahamas.

"There have been strong rumors coming out of Scientology that John Travolta is disappointed that the religion was not able to help his son more," Rick Ross, the founder of an institute dealing with "cults, controversial groups and movements," tells the paper. "It's led him to question his faith."

That would be a seismic spiritual shift for Travolta, especially given that Preston is also a longtime member -- and an outspoken one, at that -- of the L. Ron Hubbard-founded religion (by the by, she recently returned to work on Miley Cyrus' new movie, "The Last Song").

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His devotion to the "Dianetics"- and E-meter-espousing church even led him to don dreadlocks and platform boots to star as an alien baddie in the critically eviscerated "Battlefield Earth," which was based on a Hubbard novel.

When we contacted Travolta's spokeswoman about the state of his well-being and his current relationship with the Church of Scientology, she was quick to denounce the claims, telling us, "The story is categorically not true."

Echoes a second mouthpiece to People magazine, "There's no change in the relationship between the Church of Scientology and John. He is a member and it's as it was, now and forever."

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