Alicia O'Reilly was found dead in her bed in her Avondale home on August 16, 1980.
It appears she was killed while her eight-year-old sister slept just metres away.
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Despite a lengthy initial investigation, and multiple reviews, her killer has never been found but Auckland police have recently been re-investigating the case.
New Zealand Herald investigative reporter Jared Savage wrote a special report on the case. He says although some physical clues were left at the scene, matching DNA to suspect samples was science fiction in 1980.