Not enough: sister's grief at killer's 11-year sentence

Mr Sullivan's sister Feauina said Allen had ruined not only their lives but his own.

"Nothing's going to bring my brother back," she told AAP outside the Victorian Supreme Court on Tuesday. 

"Whatever the number was today, we were never going to feel like obviously it was enough. 

"My brother's just not coming back and we have to live with that for life."

Allen was with two teenage boys on January 16, 2024, when he attacked Mr Sullivan at a Carlton apartment building in Melbourne's inner north.

Mr Sullivan had arrived home on an electric scooter and got into the elevator to go to his apartment about 11.30pm with the three young men.

Allen had a tartan scarf around his face and was armed with a kitchen knife, and the group discussed an earlier fight.

Mr Sullivan tried to calm the young men down, but within minutes Allen stabbed him inside the elevator as he tried to fight back and escape.

Allen then fled the scene and escaped interstate to Queensland, where he was arrested and extradited to Melbourne on February 17.

Supreme Court Justice Stephen Kaye said Allen had killed a complete stranger who was unarmed, outnumbered and defenceless.

"He posed no threat to you," Justice Kaye said in sentencing.

"You have taken a life of an entirely innocent person who was quite clearly a decent and much-loved member of his family."

The judge found the manslaughter was premeditated rather than a spontaneous outburst and Allen had fled the scene without calling for help for Mr Sullivan. 

Justice Kaye said those factors made it a more serious example of manslaughter, which needed to be denounced to the public.

Knife crime among young people was also prolific and must be met with stern sentences, he said.

But Justice Kaye also noted Allen's personal circumstances, including his disadvantaged upbringing, extensive drug use and diagnosed post-traumatic stress disorder and depression.

Allen had also entered a guilty plea at an early stage, shown genuine remorse and taken steps in custody to reform himself ahead of his eventual release, the judge said.

In sentencing him for the manslaughter and an unrelated armed robbery, Justice Kaye jailed Allen for 11 years. 

But Allen could be eligible for parole in just over six years, having already spent more than a year behind bars.

Allen's mother broke down in tears and yelled out "love you my son" as he was led from the courtroom. 

Feauina Sullivan said she wanted her brother Andrew to be remembered as the sweetest person who was cherished by his many family members and friends.

His friend Scott Bowmaker said Mr Sullivan was the type of person who would give the shirt off his back to anyone who needed it.

"We weren't expecting any sentence today that would would satisfy us because he's not coming back," he told AAP.

"Whatever sentencing period (Allen) has is not enough because at some point in time, he will be a free man."