Acclaimed Hollywood director Steven Spielberg says Roald Dahl's family had nothing but "lovely things" to say after seeing his adaptation of the beloved children's book, "The BFG."

Spielberg, who has a long track record of directing buckswashling adventure and delumptious drama films, says he was pleased to have the Dahl family's endorsement with this adaptation, although his harshest critics belong to his own family.

"There was pressure from my own children to do the book justice because when they were very young, I read the book out loud to a lot of them," Spielberg told CTV News Channel on Tuesday, from Los Angeles. He added that the film helped renew his "faith in childhood," which he believes can be a hard thing to hold onto in the face of depressing world events.

"It's important to remember that we never lose (our childhood)," Spielberg said. "I still dream those dreams, and I still want to share them with everybody."

The three-time Oscar winner said he stayed true to the dark elements in Dahl's original book, while also making the film child-friendly in the tradition of classic Walt Disney films such as "Snow White," "Dumbo" and "Fantasia."

"They all have those sort of nightmarish interludes but… you eventually get out of the dark and there's redemption," Spielberg said. He promised the film will be "about 80 per cent happiness," and that there are "dreams galore through 'The BFG.'"

Speaking to CTV News on the day after the 41st anniversary of the release of "Jaws," Spielberg admitted the shark film remains the biggest-ever challenge he's faced in his career – bigger even than shooting "The BFG."

"It was the toughest production I ever endured," Spielberg said of "Jaws," as he recalled the gruelling eight-month film shoot that was hampered by harsh ocean conditions, and a frequently malfunctioning mechanical shark prop. At one point, Spielberg thought he'd have to beg Martin Scorsese for a film editing job because he thought "Jaws" would fail, he said.

"I really believed my career was over. It was going to be a two-movie kid," he said.

Instead, "Jaws" became one of the first true summer movie blockbusters, with a gross domestic take of $260 million at the box office in 1975. Adjusting for inflation, that number would equate to $1.01 billion in 2016, according to the website Box Office Mojo.

Spielberg's adaptation of "The BFG" stomps into theatres July 1, with Mark Rylance starring as the BFG. Rylance won the Academy Award for Best Supporting Actor earlier this year, for his role in the Spielberg-directed "Bridge of Spies."