The sister of Greenough axe murder victim Karen MacKenzie says she will never have peace until her killer, William Patrick Mitchell, is dead.
Mitchell's bid for freedom was denied by Western Australia's Attorney-General Michael Mischin on Monday, 20 years after the brutal 1993 murders of Ms MacKenzie, 31, and her children Daniel, 16, seven-year-old Amara and Katrina, five.
Still considered one of Western Australia's most horrific crimes, the state's Prisoners Review Board considered Mitchell's case and sent a report to the government.
After consideration, and meeting with the victims' family, Mr Mischin denied Mitchell's parole on Monday.
While saying she was relieved at the decision, Evalyn Clow said she will face the same fight in September 2016, when Mitchell can appeal for parole again prior to his next statutory review date.
"Mitchell is behind bars for another three years, but we will have to do this fight over and over again, until either he dies or I do," Ms Clow wrote on the Facebook page dedicated to keeping Mitchell behind bars.
"I'm hoping he goes before I do, so that I can have some peace back in my life."
Mr Mischin cited three factors for his decision, including the nature and gravity of the offences committed and the degree of risk to the community if Mitchell was released.
"(Also) comments made by Justice Owen during sentencing that the offences were so serious as to defy description and that as far as he was concerned, he will never be released, at least not for many years greater than the 20 years minimum for a sentence of strict life imprisonment," Mr Mischin said.
Ms Clow said she wanted changes to parole laws so families of any future victims would not have to face the same stresses.
"Now what we have to do is get the legislation changed to help future families who are victims of crime from going through continual hell of fighting to keep killers behind bars," Ms Clow said.
"It won't help us because Mitchell was jailed under the current legislation, but if we can help future victims that has got to be better than the lack of regard for the victims and their families at the moment."
But Mr Mischin said a change was unlikely.
"The law requires all life terms are reviewed every three years, I can't make exceptions in a particular case," he said.
Mitchell was originally sentenced to an indefinite term of prison, but that decision was overturned in 1996.
He was transferred to medium security at Bunbury Regional Prison in 2009.
Ms Clow said she felt like her, and her family, were serving a sentence.
"Living with this situation is an extremely stressful and painful life. I can tell you now that my life and that of my family has been more torturous than anything Mitchell has to deal with," she wrote.
