Michelle Buckingham's mum never got over the 16-year-old's body being left on the side of a little-used rural Victorian road "like a dead dog".
Elvira Buckingham remained broken hearted when she died in September, 32 years after her daughter's "nightmare" murder and only five days before Steven James Bradley went on trial for her murder.
Bradley, 54, has now been jailed for 27 years for the brutal and cowardly murder a Victorian Supreme Court judge found was committed with two others.
There was a nightmare quality to the cruel brutality of Bradley's offending, Justice Robert Osborn said.
It was a heartless and predatory attack upon a teenage girl who had her whole life ahead of her.
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Bradley, then 21, picked up Michelle in Shepparton on October 21, 1983, and with two teenage friends killed her when she refused to have sex with him, the judge, sitting in the regional Victorian city, said on Tuesday.
She was stabbed at least 19 times in the back in a Shepparton pub car park and her body dumped beside a Kialla road where it was found, badly decomposed, a fortnight later.
A part of her mum died that day, Michelle's sister Karen Dewar said.
"Her grief was indescribable. She couldn't understand how someone could do that to her precious daughter, who was kind, caring and well liked," Ms Dewar said in a victim impact statement.
"What hurt mum the most was how they left Michelle's body, lying there like a dead dog. That's what struck her to the core."
Justice Osborn found Bradley killed Michelle with two 16-year-old friends, both of whom have denied any involvement.
The judge said neither man had legal representation during the former dog groomer's trial and the evidence against them was essentially hearsay and would not be admissible in a criminal prosecution.
Bradley's brother-in-law Norman Gribble had revealed Bradley, highly distressed and bleeding from a cut on his hand, had confessed "I've killed someone" and "we killed someone" the day after the murder and got rid of his car shortly afterwards.
Justice Osborn said while Mr Gribble did not go to police for three decades for family reasons, his evidence was substantially accurate.
In jailing Bradley for at least 21 years, Justice Osborn said he had never demonstrated any real remorse.
"The violence of the manner in which she was killed and the callousness with which her body was left by the road to rot shocked and traumatised those who were close to her," Judge Osborn said.
"Not only did you kill a young woman at the start of her adult life but you caused permanent emotional trauma to those who loved her."
Bradley had enjoyed freedom for 30 years of his adult life, Justice Osborn said.
"The time has now come to pay the penalty for the murder you committed all those years ago."
