The sister of Rachelle Childs has asked Australian authorities to reopen the investigation into the 2001 killing of the 23-year-old, offering a $500,000 reward and enlisting a true-crime podcast and a retired detective as part of a renewed bid to identify her killer.

Childs, who worked as a car saleswoman, disappeared after leaving work on a Thursday afternoon in 2001. She phoned her sister, Kristy, to confirm plans to meet for a drink that evening; the meeting never took place. About nine hours later, Childs was found partly burned in a shallow ditch roughly 70 miles from her workplace. Police have said the case was the subject of an "exhaustive" investigation, but no one has been arrested.

Kristy Childs, who was 18 at the time of her sister's death, has written to the police minister seeking a formal reopening of the inquiry. She has partnered with Ashlea Hansen, host of the Dear Rachelle podcast, and retired detective Damian Loone to review the case and press for fresh investigative steps. The podcast, which investigates the circumstances around Rachelle Childs's disappearance and death, has been downloaded more than four million times.

Authorities have previously described the original probe as thorough, but family members and the podcast team say media attention and new lines of inquiry could generate leads that were not available or pursued two decades ago. The criminal investigation concluded with Childs’s body discovered with evidence suggesting she had been assaulted and set alight, according to public descriptions of the case. Law enforcement agencies have not named any suspects or announced pending charges.

The offer of a $500,000 reward (about £240,000) accompanies Kristy Childs’s appeal for new information from the public and an official reconsideration of the evidence. The exact provenance of the reward has not been disclosed by the family or the podcast team.

True-crime journalism and cold-case reviews have in some instances prompted fresh tips or renewed forensic testing in other jurisdictions, and the family’s campaign cites such outcomes as part of its rationale for renewed scrutiny. The current status of physical evidence from the 2001 investigation, including whether biological samples remain available for modern DNA testing, has not been publicly detailed.

Police statements to date reiterate that officers conducted an extensive inquiry at the time, but they have not said whether they will accept the family's request to reopen the case or what additional resources, if any, would be made available. Kristy Childs and the podcast team say they hope public interest and newly surfaced information will persuade authorities to re-examine leads and any remaining forensic material.

The appeal highlights the continuing impact of unsolved violent crimes on families and the role relatives and media collaborators increasingly play in seeking answers. The Childs family has urged anyone with information, however small, to come forward to assist investigators.

Local police departments have not provided a new timeline for any re-examination of the case. The family and their collaborators say they will continue publicising the case and pursuing every avenue to identify the person or persons responsible for the death of Rachelle Childs in 2001.