Nearly four years ago, Ardavaz Delir lost his son in a way no parent would want to imagine.
Eden Delir was 17 when he was surrounded by a group of gatecrashers at a Sydney Halloween party, savagely bashed and struck on the head with a wine bottle with such ferocity it smashed.
Eden was found lying unconscious and covered in blood beside a nearby house, where he ran to try to save himself before collapsing.in
He never regained consciousness and died in hospital a week later from head injuries.
On Friday, the teenager who delivered the fatal blow was sentenced to at least seven years jail for manslaughter.
The 18-year-old, who cannot be named because he was 15 at the time, was handed a maximum jail term of 10 years.
Last November, he had been found not guilty of murder but guilty of manslaughter.
Ardavaz Delir said he knew the sentence would not bring back his son, but he was glad Eden's life had been given a value by the court system.
"Two or three years, that would have been a slap in the face," he said outside the NSW Supreme Court.
"When you see in the media what's happening with some unrealistic sentences, we are pleased by it."
In handing down the sentence, Justice Peter Hall told the court the attack was unprovoked and brutal.
The offender sat impassive in the dock as Justice Hall acknowledged the "exceptionally painful and tragic" ordeal Eden's parents continued to endure.
Eden's mother, Dorothy, who sat next to her husband, held her hand to her mouth for the entire proceedings.
The court heard that soon after the gatecrashers arrived at the party, they recognised Eden as someone they had once robbed, with one of the six young men pointing at him and saying, "That's the guy that snitched."
The boys, one of whom a witness said wielded a tubular metal pole, surrounded the 17-year-old, punched him to the ground and kicked him in the head and body.
The offender then smashed the glass bottle over his head.
Justice Hall said the fact the young men outnumbered Eden without any warning and continued to inflict blows even after he fell to the ground outlined the "complete callousness" of the crime.
The teenager will serve the beginning of his sentence in a juvenile facility, and will be transferred to an adult jail when he turns 21.
He will be eligible for parole in October 2020.