John Travolta is opening up about to ET about how he was able to deal with the devastating death of his son Jett in 2009.
The 61-year-old actor plays an art forger getting out of prison to be with his sick son in his new film The Forger, which hits theaters and On Demand this Friday.
"I dealt very specifically with my actual loss in life and had a lot of help dealing with it," he tells ET about parallels between his intense new role and his real-life. "I try not to collapse my art with real experiences, but in this particular case I think it was reflective or informed my performance to some degree. I tend to act in the moment."
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Jett, the eldest child of Travolta and wife Kelly Preston, passed away when he was 16 years old while on a Christmas vacation in The Bahamas. According to his Bahamian death certificate, the cause of death was a seizure.
"We had a very full life, my son and I, 16 years," he reflects. "We did travel the world and he saw every place by the time he was that age, but you plan on a life that's a lot longer for your child and you always intend to go first, so that's the difference. Regardless of the full life we did live together, you wanted a full life for him. Everyone does -- every father wants the future of their child to be a full-bodied life."
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Travolta, a well-known Scientologist, credits his church for helping him deal with his loss.
"After my loss I had two years of full-time help from my church," he reveals. "They never left my side, and I got through a time that I didn't think I was going to make it. I really didn't, several times, but they pulled me through. So that's where my basic strength for moving on came from."
The controversial religion has come under fire lately, especially since HBO's much talked-about documentary Going Clear: Scientology and the Prison of Belief aired late last month. However, Travolta says he doesn't feel the need to "defend" his religion.
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"I don't really feel like I defend it," he tells ET. "I feel like I tell the truth about what it is for me. And that handles it because, 40 years, it's been amazing. I've saved other people's lives, I've saved my own life several times. I'm still here, sitting, talking to you. I've had nothing but great results."
"It works, it's very successful," he says. "It shows by the growing amount of people interested in the subject matter. I tend to look at that, rather than attacks of any sort."
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Earlier this month, Travolta told The Tampa Bay Times that Scientology has been "beautiful" for him, and called the HBO documentary "negative." Watch below: