Michelle WilliamsMichelle Williams has reportedly told two year old daughter Matilda that her dad Heath Ledger has “gone away” following his death last month.

A source close to the former Dawson’s Creek star told Us Weekly: “Michelle was always really vulnerable, so this has shaken her quite a bit. She’s mourning and trying to figure out what to do next.”

“Michelle and the family are showering Matilda with love right now to cushion it so she isn’t really aware. [She] is too young to understand.”

“Michelle basically told Matilda, ‘Daddy went away.’ Matilda still doesn’t grasp it.”

On Tuesday, Michelle and Matilda arrived in Australia ahead of Heath’s funeral in Perth at the weekend.

In related news, the US Drug Enforcement Administration have launched an investigation into how Heath acquired the prescription drugs that killed him.

Yesterday the New York Chief Medical Examiner’s Office announced that Heath died of an accidental overdose of opiates and benzodiazepines, all of which had been obtained on doctors’ prescriptions.

A spokesperson for the agency said yesterday: “It’s an ongoing investigation by the New York Police Department and, as always, we’re standing by to assist other investigations.”

“We’re [also] trying to educate that legal drugs - these prescription drugs - can be just as dangerous as more hardcore drugs when misused or abused. Sad to say, this is a perfect example of how even the so-called ‘safe drugs’ can cost somebody their life.”