Mike Nichols, who directed Travolta in 1998's Primary Colors, tells PEOPLE: "They're very strong. They have Ella. They have lots of people they love to take care of. And they will. But they have to have time for just plain grief."
A source close the family tells PEOPLE that the autopsy on their 16-year-old son Jett revealed his death Jan. 2 in the Bahamas was caused by a "seizure disorder." Because there was no foul play, the body was released immediately to the Travolta family.
"There's probably nothing in the world that is harder for a parent than losing a child, so for both of them, I just ... I just can't imagine anything more difficult," says family friend Anne Archer. "I think what's most important is that friends and family and the community collectively put their arms around them and hold their thoughts for them and help support them through this time."
'Kind and Decent'Sherry Lansing, the former CEO of Paramount and a longtime Travolta friend, says Travolta and Preston are "two of the kindest, most decent people, and everything is about their family and everything is about their children."
"I cannot begin to imagine the depths of pain that somebody feels when this happens," she says. "It's just the worst of anything that could ever happen to anybody."
Dancing with the Stars judge Bruno Tonioli, a friend of Preston, said the actress is "a wonderful lady, a wonderful mother" to whom he sends his "deepest sympathy."
"He was their pride and joy," says Tonioli. "Their children are everything to them. There are no words to express how sorry I am; I am at a loss for words."
A Father FirstAmy Pascal, co-chairman of Sony Pictures Entertainment, who has known Travolta since they worked together on the 1996 film Michael, says the actor has always been a devoted family man, now suffering a great loss.
"He was a father first," says Pascal, who wrote to the family upon hearing the news of Jett's death.
Travolta's Wild Hogs costar Tim Allen says he and his family wanted to "extend our condolences to John, Kelly and Ella. We know how much they loved and adored Jett and words cannot express how sad we were to hear about his passing."
Reporting by MARY GREEN, BRENDA RODRIGUEZ, EUNICE OH and SARA HAMMEL
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