Grant Alfred Beaumont’s death was announced in the funeral notices in Adelaide, 57 years after his children vanished.
The elder Beaumont, who was also known as Jim, died aged 97 on April 9.
“Loved father of Jane, Arnna and Grant,” the notice read.
“Reunited in heaven.”
No one has ever been charged with their abduction though there have been many suspects over the following decades.
Police believe the three children were murdered.
Police are yet to close the case, and a million-dollar reward remains for anyone who can solve it.
The elder Beaumont separated from his wife Nancy in the early 1970s.
He was privately cremated, the death notice stated.
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