Heath Ledger's sister refutes claims that Joker role was responsible for his death

Heath Ledger's sister, Kate Ledger has said the actor's role in "The Dark Knight" was not responsible for his untimely death from a prescription drugs overdose in 2008.

Ledger's sister refuted the claims that the actor was suffering from mental health issues at the time of his death, reported The Telegraph.

"I was really shocked, because that was him (Ledger) having fun. 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!" Kate said at the premiere of "I Am Heath Ledger" at the Tribeca Film Festival.

Producer of the documentary, Matt Amato added, "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."

Ledger was 28 when he was found dead in his New York apartment on January 22, 2008, barely months before the release of the Christopher Nolan film.

The actor was awarded the 2009 Oscar for best supporting actor for the film posthumously.