Elton John‘s new documentary Never Too Late arrives on Disney+ Dec. 13 — but only because his two sons, Zachary and Elijah, gave it the thumbs up.

Speaking to Collider, David Furnish, Elton’s husband, manager and co-director of the film, says their older son, Zachary, doesn’t like being filmed at all, so it was nearly impossible to get him to appear in the documentary.  However, there’s one important scene where Elton is shown talking to both boys on FaceTime.

“I did have to sit down with both boys at the end and screen the whole film for them and get their permission because when we started filming, they were like, ‘Well, hang on a minute. We don’t know if we want to be part of this,'” Furnish explains. “And I said, ‘Don’t worry, we’ll show you the whole film, and if there’s anything you don’t like, we will take it out.’”

Furnish says when the kids saw the movie, they were concerned their friends would tease them about the FaceTime scene because, he says, “They were like, ‘Oh my God, we’re so young! We’re talking like babies.'” But eventually, Furnish says, “We talked about the greater message that the film could put out, because we do talk with the boys about the fact that same-sex parenting is not everybody’s cup of tea.”

“The fact [is] that a scene like that in a film can be a very … powerful piece of advocacy, and it could maybe change people’s minds and maybe make people think more positively about it,” he adds.

By the way, there’s a brand-new Elton song in the film. Like the film, it’s called “Never Too Late,” and Elton co-writes and performs it with his friend Brandi Carlile.

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