Sylvester Stallone makes rare candid comments on son’s tragic death

Sylvester Stallone has reflected on his relationship with his late son, Sage.

Stallone's son died in 2012 at the age of 36, which a coroner later determined was a result of heart disease from atherosclerosis - despite initial reports that it was drug related.

The Rocky star shared his son with ex wife Sasha Czack, with whom he also shares another son, 44-year-old Seargeoh Stallone.

Since Sage's death, Stallone hasn't spoken out much about his son's passing - but has made some rare and candid comments about him in his new Netflix documentary, Sly.

Sage starred as his father's on-screen son Robert in Rocky V, which Stallone says wasn't a dissimilar relationship to theirs away from the cameras.

When asked if the movie plot reminded him of his real-life relationship with Sage, Stallone says: "Unfortunately, yes."

He goes on: "I try to take something that actually is what I wish I had done in real life, but I wasn’t able to do that in reality. And so quite often I would do it theatrically, magically."

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"A lot of that is true," Stallone added.

"Unfortunately, you put things before your family. And the repercussions are quite radical and devastating."

As well as present day filming, Sly also shows scenes from the premiere of Rocky V where Stallone gushed about fatherhood while stood with his son.

"There’s a line in the movie, ‘I’m so glad he’s born because now I can live through your eyes.’ That, I think, is what fathers look to their children for," he said at the time.

"It’s an extension of, a slice of immortality. As long as he’s alive, your memory will always be alive, that you did something right. I mean, you hope for that."

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Elsewhere in the new documentary, Stallone talks about his life-changing injuries sustained on the set of The Expendables.

In 2009, during the shooting for the film, the now-77-year-old suffered an injury while performing one of his own stunts, and he's since revealed he's 'never fully recovered' from it.

Stallone was left needing surgery and ended up with a metal plate in his neck.

"Truthfully, I never fully recovered," the actor says in Sly.

"It did such a number on my body, I've never been the same."

But, financially, the actor's injuries paid off as The Expendables franchise has seen him make $51 million.

But that's arguably pocket change for Stallone who, as of this year, is said to be worth a staggering $400 million.