One of the men allegedly involved in Irma Palasics' murder more than two decades ago remains at large and unknown to authorities.
Though police have arrested and charged 68-year-old Steve Fabriczy with murder, Mrs Palasics' grandson John Mikita has urged the second offender to reveal himself.
"We call upon the second offender to come forward and let police know who they are," he told reporters on Friday outside ACT Magistrates Court.
"There are many questions that we have as a family need answers to."
In November 1999, two men forced their way into Irma and Gregor Palasics' McKellar home, where they bound and violently assaulted the couple before ransacking their house.
Mr Palasics freed himself from his bindings, which included cable ties, duct tape and a telephone cord, and found his wife had died from injuries sustained in an alleged assault by one of the burglars, Melbourne Magistrates Court was told on Thursday before Fabriczy was extradited to the ACT.
The 72-year-old woman was found face down in the hallway, with bindings covering her hands, mouth and ankles.
An autopsy later revealed she had suffered a broken nose during the home invasion.
Two decades later - in 2019 - police found Fabriczy's DNA was allegedly a match to forensic evidence from the crime scene.
Steve Fabriczy, 68, appeared at ACT Magistrates Court in Canberra on Friday morning when he was officially remanded in custody over 1999 home invasion .
He had not applied for bail or entered any pleas but representatives said he would be applying for legal aid.
Mr Mikita said seeing the man in person was a "highly emotional experience".
"My grandparents did not deserve what happened to them on that night," he said outside the court.
"It just shocks us - how old (Fabriczy) is now. It's unbelievable."
According to police at Thursday's extradition hearing, 68-year-old Fabriczy allegedly admitted being in the Palasics' home on the night the woman was killed but denied assault or murder during a September 8 interview.
Fabriczy also attempted to apply for extradition bail on but was denied after the prosecution argued he was a flight risk with plans to move back to his home country of Hungary and significant financial means.
He could also speak to his co-accused, who remains at-large in the community, the prosecution said.
Fabriczy was previously convicted for plotting to hijack $1.6 million worth of cigarettes, the court heard.
The case will return to court on October 5.
