The former chief detective in the William Tyrrell case has expressed his heartbreak at learning the missing boy’s foster grandmother has died.

William Tyrrell’s foster grandmother, who was one of the last two adults to see the boy alive, has died.

The woman, who cannot be named for legal reasons, owned the house on the NSW mid-north coast where William was staying when he went missing.

Gary Jubelin told Ben Fordham it “puts things into perspective”.

“I know it would have given her a great deal of comfort before her passing if she had some answers about what happened to William.”

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