Heath Ledger's sister talks about her brother's time as the Joker in tender new interview

Heath Ledger’s sister has opened up about her brother and his tragic early death in 2008, ahead of the release of a new documentary about his life that has been sanctioned by his family. 

His death, from an accidental overdose of various prescription drugs, shocked the world. Many people at the time blamed his bravura performance as the Joker in The Dark Knight, which had wrapped just a few months before, but according to Kate Ledger, this – and other rumours that he’d been struggling with his mental health – is false.

Speaking at a Q&A before the premiere of I Am Heath Ledger at the Tribeca Film Festival, the Telegraph reports that Kate denied that method acting as one of the great movie villains had any role in his death.

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"I was really shocked, because that was him having fun," she said. "Every report was coming out that he was depressed and that [the role] was taking this toll on him, and we're going, honestly, it was the absolute opposite. It couldn't be more wrong. He had an amazing sense of humour, and I guess maybe only his family and friends knew that, but he was having fun. He wasn't depressed about the Joker!"

The documentary has been put together in part by a lot of footage Heath, an apparently obsessive film-maker in his own right, had shot of his life. Its producer Matt Amato echoed Kate’s words, saying: "I hope it's an antidote to a lot of the gossip that exists in the world. There are some really terrible things about Heath out there."

The actor died in New York at the age of 28, a few months before the film was released. His work earned him many posthumous awards including a Golden Globe and an Oscar. Rumours that the role had affected him were fueled by an interview with the New York Times, in which he admitted: "Last week I probably slept an average of two hours a night. "I couldn't stop thinking. My body was exhausted, and my mind was still going."

But while the new documentary doesn’t comment directly on the circumstances surrounding his death, it does reveal that he’d always had trouble sleeping.

I am Heath Ledger will premiere on May 17.