Ledger killed by drug mix.
The Brokeback Mountain star took two antianxiety drugs including Valium, two types of sleeping pills and painkillers Oxycontin and ibuprofen.
Distraught dad Kim said yesterday: "Heath's accidental death serves as a caution to the danger of combining prescribed drugs. It proved lethal for our boy." Ledger, who spoke openly of taking stress pills, was found in New York on January 22.
Meanwhile former fiancee Michelle Williams, 27, flew to Australia for his private funeral, thought to be on Saturday.