In a candid new interview with Esquire Spain, John detailed his experience with grief as he explained every journey is "different" for someone else.
WATCH: A look back at Kelly Preston's life
"I have learned that mourning someone, mourning, is personal," he said. "Mourning is individual and experiencing your own journey is what can lead to healing.
"This is different from someone else's journey. The most important thing you can do to help another when they are in mourning is to allow them to live it and not complicate it with yours. That's my experience."
The 67-year-old is a doting father to two children, Ella, 21, and Ben, 10, both of whom he welcomed with his late wife Kelly. The couple were also parents to their son Jett, who died at the age of 16, following a seizure at a Bahamas holiday home in 2009.
John Travolta and Kelly had been married since 1991
John went on to discuss his kids, confessing he will help them forge their own careers. "I will ensure the future of my children, help them with what they want to do with their lives," he added.
"It is what I do with Ella now with her films and teaching her to work in the profession. Ben is barely ten-years-old. I want to help him evolve because he has his whole life ahead of him."
His wife Kelly was perhaps best known for starring alongside Tom Cruise in Jerry Maguire, but she also appeared in Space Camp, What A Girl Wants, Twins and For the Love of The Game.
Her last role came in the 2018 film Gotti, where she played Victoria Gotti, the wife of Mafia boss John Gotti, who was portrayed by her husband.
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