The fact Luke MacKenzie was killed by a drink driver is not the hardest part for his parents to bear.
After causing the head-on collision, 27-year-old Xingyu Shang pulled himself from the wreckage, grabbed his phone and flagged down a motorist to get a ride home.
No checking for signs of life. No call for an ambulance.
Shang will be sentenced this morning in the Manukau District Court after admitting charges of careless driving causing death, while under the influence of alcohol, and failing to stop after a crash.
Despite their deep grief in the two years since the accident, Tania and Martin MacKenzie have made an incredible gesture to the man who left their son to die.
After an emotional restorative justice conference with Shang and his family - followed a few days later by a group visit to Purewa Cemetery to pay their respects - the couple were asked to make a recommendation to the court. They knew the judge's decision would be finely balanced: home detention or jail.
The MacKenzies told the court they did not want Shang locked up.
"He's ruined our life and we've lost our son but we don't necessarily want his life to be ruined," Mr MacKenzie said.
They did not want their position to be mistaken for absolution.
"We haven't forgiven him. We've accepted what his situation is."
They knew their stance would not find favour with all Luke's friends, many of whom want to see Shang behind bars.
But the couple said they refused to be consumed by a grudge that would not bring back their son.
According to court documents, the cause of Luke's death was "positional asphyxia; being left in his car with no immediate first aid".
It states Luke's chest and neck were forced into the frame of the door by the impact of the collision, which rendered him unconscious.
But police and the coroner told the family Luke would have died regardless of Shang's actions immediately after the crash.
Though Mr and Mrs MacKenzie accepted his genuine remorse "at face value", they did not get all the answers they wanted when they finally sat down with him.
The defendant put his actions after the crash down to being "dazed".
"We still struggle with that," Mr MacKenzie said. "The only way we can get past this is that he made an error. He made a judgment call and it was wrong. From our point of view it meant our son passed away with no one there with him."
The tragedy changed their lives forever but the family said the long-winded legal process proved almost as tortuous. "We've been absolutely frustrated. Frustrated to hell," Mr MacKenzie said.
Initially, Shang pleaded not guilty and the case was three days away from trial. MacKenzie family members even came over from Australia to attend but yet another adjournment in the meandering legal process meant their trip was wasted.
"For close on a year, not knowing whether our son was at fault and the other party not taking responsibility, that was soul-destroying," Mr MacKenzie said.
Today, he will pay tribute to his son in a statement in court.
Do not call it closure, though.
"The sentencing is just part of the grieving process - there is no closure for us ... we're constantly reminded of Luke."
Shang will eventually be deported to China.