Karen Davies’s brother Ray was murdered in the Snowtown serial killings.
Karen said she was living in a women's shelter at the time and kept asking the staff if her brother had rung or left a message.
Bunting and Wagner were the main offenders involved in the "bodies in the barrels" killings, which involved 12 deaths between 1992 and 1999.
Accomplice Mark Haydon was released into the community in 2024 after spending 25 years in jail.
James Vlassakis is set to be released on parole after a decision was upheld last week, despite the SA government's attempt to keep him behind bars.
Vlassakis is expected to arrive at the pre-release centre in Adelaide this week, where he will remain for up to 12 months.
Karen said although Vlassakis did not murder her brother, the four people he killed could never walk the streets again, so she failed to understand how Vlassakis could be given parole.
Karen said Ray was in a relationship with Suzanne Allen, who was a former partner of Bunting.
Ray lived in a caravan on Suzanne's property and is believed to have been killed about four years before his body was discovered in 1999 at Bunting's former property at Salisbury North.
Vlassakis was 18 when, in 1998, he took part in the murder of his half-brother Troy Youde — a crime he committed at the behest of his stepfather Bunting.
The mother said families had to live with the loss forever, and she questioned how any time served could ever be enough.