Ethan Hoac, 14, was murdered on the side of a Melbourne road in an unprovoked attack that a judge described as "appalling" and "cowardly".
Three years on, the trio responsible for the murder have never explained their actions.
Today, two of Mr Hoac's killers were handed sentences of 17 years and 18-and-a-half years.
"You murdered a 14-year-old in a public street in circumstances of appalling violence," Justice Mandy Fox said.
"Ethan and his friends were targeted by you. They possessed no threat whatsoever."
Ethan Hoac was walking down the street with friends in November 2023 when he was set upon by three attackers. (ABC News)
The other murderer was sentenced in 2025 to a maximum of 17 years behind bars.
The killers were aged 17 at the time of the murder and cannot be identified for legal reasons.
Teen killed in unprovoked attack while walking down the street
Mr Hoac was ambushed while walking with two friends near the intersection of Furlong Road and Bailey Street on June 26, 2023, the Supreme Court heard.
The killers drove past in a stolen car. They circled the unsuspecting group before crashing into Mr Hoac from behind, sending him flying through the air.
Within seconds, two masked passengers jumped out of the car and began stabbing and kicking the defenceless boy, who weighed just 38 kilograms.
He suffered 30 machete stab wounds in less than a minute and died in an ambulance on the way to hospital.
"There was no connection between your group and Ethan's group. Nothing explains why you chose to attack Ethan on this night," Justice Fox said.
"The attack was random and unprovoked; it was also cowardly and committed in company."
The family of Ethan Hoac attended the sentencing of one of his killers in November 2025. (ABC News: Kristian Silva)
Mr Hoac was one of nine siblings. His mother, Annie Huynh, described him as a sweet boy who was always smiling.
"I just can't believe it's happened to my son," Ms Huynh said outside court.
"He's a beautiful boy, always positive, always making people laughing, happy."
After attending dozens of court hearings, Ms Huynh hoped today would be her last.
She said she wanted the killers to "learn from this mistake".
Driver of car shows no remorse over murder
All of Mr Hoac's killers endured difficult childhoods, marred by domestic violence and drug abuse, the court heard. All left school early and chalked up criminal records for crimes like assaults and carjackings.
Even after Mr Hoac's murder, the trio were allegedly involved in a large riot at the Malmsbury youth prison in October 2023.
The teen sentenced last year wrote disturbing rap lyrics glorifying violence while in jail.
The driver of the car that struck Mr Hoac had shown no remorse and refused to board the prison van to court today. He faced court via video link from a youth prison, showing no emotion and keeping his arms crossed during the hearing.
His 18-and-a-half-year sentence was the longest jail term of the group. He received no sentence discount because he pleaded not guilty and was found guilty by a jury at trial.
Another, who was jailed for 17 years, entered an early guilty plea and wrote an apology letter to Mr Hoac's family.
"I accept your letter is genuine and you have developed some remorse," Justice Fox told him.