Clinton Austin wanted to share his passion for art with others and dreamed of becoming an Aboriginal art teacher before he died in custody in 2022.

The 38-year-old Gunditjmara and Wiradjuri man, who passed away in Loddon Prison on September 11, 2022 - having been eligible for parole in January of that year - was a "kind and generous" person with a "big heart," his family said.

Speaking at the beginning of the inquest into his death, his twin brother Shaun said, "Clinton was not just my twin brother, but my best friend, mentor and teacher, who taught me so much about our culture [and] where we came from".

"He was a proud Gunditjmara and Wiradjuri man and a devoted father."

Mr Austin had been sentenced to three and a half years in prison for aggravated burglary and other crimes in November 2020 but had been eligible for parole eight months earlier. His family say there "are a lot of questions about what happened in the lead up" to his death that are unexplained.

"As a family, we have spent a lot of time wondering what happened and why," Shaun told reporters outside the Coroners Court on Monday.

"Why would a 38-year-old man suddenly die in prison?"

The father and a well-known artist had struggled with mental health issues and drug addiction, and, along with other prisoners in Victoria, experienced periods of isolation due to the Covid-19 lockdowns.

His family said they hoped the inquest would bring about answers into his death, as well as meaningful and long-term change to the system which has seen nearly 600 Indigenous people die in custody since the Royal Commission into Indigenous deaths in custody.

Surrounded by family wearing shirts emblazoned with Clinton's face and the slogan "Make Change," Shaun said despite his brother's troubles, he was a kind and compassionate man, "deeply loved by those who knew him" who was working hard to be "reunited" with his son.

"[it] breaks my heart that this reunion will never happen," he told reporters.

"He would always talk to me how he had his heart set on turning his life around and doing the right thing… I know he would have gotten there…

"I stand here today surrounded by our family. We are all here for the same reason: to get justice for Clinton and make a real change. I believe that my brother deserved better from the justice system, and it failed him."

A passionate artist who learned to paint, as well as reconnect with his Aboriginal culture, whilst in prison, he was completing on average two paintings a day.

"He wanted to share his talent and passion for art with others by being an Aboriginal art teacher," Shaun said.

"This was his dream. He mentored other prisoners to help them with their art."

The Victorian Aboriginal Legal Service (VALS), who is representing Clinton's family throughout the Inquest, said in 2022 they had "serious concerns about the quality of healthcare provided to Aboriginal and Torres Strait Islander people in prisons in Victoria".

"We call on the State Government to urgently address this issue and provide healthcare in prison that is equivalent to that in the community and that is culturally safe," VALS' chief executive, Nerita Waight, said in 2022.

Last year, an inquest into the death of 32-year-old Yorta Yorta and Gunaikurnai man Joshua Kerr, who died in his cell as staff watched due to flawed protocols, was labelled a "preventable tragedy" by the coroner.

His mother Donnas Kerr said at the time: "The Coroner found today that Josh's death was preventable. How many times do we have to hear these words before we take Aboriginal deaths in custody seriously?"

Clinton's family said they hope recommendations from the inquest will lead to "meaningful and significant changes" in the prison health care system to ensure the health and wellbeing of prisoners across the state is "properly taken care of".

"To my brother and my best friend, I will not stop fighting for you," Shaun said.

"I will fight to make a change, any change possible, not only for the Aboriginal people going through the justice system but anyone who has to go through it. I know that is what Clinton would want."

The inquest before Coroner Ingrid Giles is scheduled to take three weeks.