Ledger's father Kim, who accepted a posthumous acting award on his son's behalf at the 2009 Academy Awards for his best supporting role as the Joker said they want to be keep the actor's memory alive for his daughter, said The Hollywood Reporter.
"She (Michelle Williams) is aware the Oscar remains secured with the museum. At the end of the day, everything is there for Matilda, and when she can take possession of it, it's all hers," Kim said.