LOS ANGELES (Reuters) - Heath Ledger won the best supporting actor Oscar Sunday for his performance as The Joker in Batman movie "The Dark Knight," with the award hailed a fitting tribute for the Australian actor who died a year ago.
Ledger, 28, who was found dead in his New York apartment 13 months ago after an accidental prescription drug overdose, was the hot favorite to win the award which made him only the second actor to receive a posthumous Oscar.
Peter Finch was awarded an Oscar for best actor two months after dying from a heart attack for his role as a TV anchorman in the 1976 film "Network."
"This award tonight...validated Heath's quiet determination to be truly accepted by you all here, his peers, in an industry that he so loved," said Ledger's father, Kim, as the actor's family accepted the Oscar on his behalf.
The chilling Joker played by Ledger helped power the Batman sequel to a global box-office gross of more than $1 billion and made him the hotly tipped and emotional favorite to win the Oscar.
"We really wish you were here, but we proudly accept this award on behalf of your beautiful Matilda," his sister Kate Ledger told the glitzy Oscar ceremony.
Matilda, his three-year-old daughter with actress Michelle Williams, his former fiancee, will receive his Oscar when she turns 18, the Academy of Motion Picture Arts and Sciences has decided.
Although never an A-list global celebrity before his death, Ledger earned widespread attention in 2001 as the jousting squire in the action romance "A Knight's Tale" and later won critical acclaim for smaller parts in "Monster's Ball" and the Bob Dylan-inspired movie "I'm Not There."
He was nominated for an Oscar for his 2005 role as a gay cowboy in "Brokeback Mountain" but did not win the prize.
But this time, Ledger picked up virtually every award for playing The Joker -- a Golden Globe, British BAFTA, Screen Actors Guild and a slew of U.S. and Australian critics awards.
In Australia, tributes for Ledger began flowing after news of his win. Arts Minister Peter Garrett interrupted the Australian parliament to announce the award.
"This incredible award for this actor cements his place as not only one of the finest actors of his generation, but of our entire film history," Garrett told parliament.
Others hoped the Oscar would finally bring an end to the buzz around Ledger who has continued to be in the news since his death with Oscar speculation and fighting over his will.
Dr. Vincent O'Donnell, media commentator from Melbourne's RMIT University, said it would have been hard not to award the Oscar to Ledger after the momentum built over the past year.
"Hollywood is a dream factory and it is about the future and not the past so it is terrific that he won because he was an actor of very great potential," O'Donnell told Reuters.
"Honoring someone posthumously, you would expect an aging director or producer who had given their life to Hollywood, but there was such a strong emotional push that it would have had to be a very remarkable supporting actor to have beaten Ledger this year. No one had that same emotional appeal."
(Additional reporting by Belinda Goldsmith and James Grubel in Canberra)
Reporting by Jill Serjeant; Editing by Mary Milliken