Kallista Mutten, the mother of murdered nine-year-old Charlise Mutten, expressed profound regret for trusting her daughter's killer, Justin Stein.

Charlise was reported missing on January 14, 2022, after asking to accompany Stein back to his home on January 11.

Stein was convicted of murdering Charlise and hiding her body in a barrel near the Colo River, receiving a life sentence in August 2023.

The tragic incident occurred during a Christmas holiday in the Blue Mountains, where Stein fatally shot Charlise.

Kallista met Stein in prison in 2018, and they began a relationship after their release, believing they could create a better life together.

Toxicology tests indicated that traces of Seroquel, an anti-psychotic medication prescribed to Stein, were found in Charlise's system.

Prior to the murder, Charlise had stayed with Kallista and Stein, both of whom were struggling with drug addiction.

Justice Helen Wilson described Stein's crime as 'unspeakably vicious' and highlighted its heinous nature during sentencing.

Charlise had been living with her grandparents but was allowed to spend the holiday with her mother and Stein.

In an emotional interview, Kallista referred to Stein as a 'monster' and 'pure evil', reflecting on the horror of the situation.

Kallista acknowledged her failures as a mother, expressing a desire for Charlise to be remembered as a joyful and kind person.

Charlise's body was discovered on January 18, 2022, showing multiple gunshot wounds, further underscoring the brutality of the crime.