Imagine arriving at hospital to find your beautiful son on life support. Imagine being told there was nothing anyone could do to save him.
Imagine being told he was brain dead. Imagine being told he was "king-hit" from behind and never stood a chance.
Imagine being told, once you turn off life support, he will die.
It's like murder, isn't it? It's bloody serious and the community rightly wants tougher sentences. It's a natural reaction to somebody hitting someone and they die.
Let me tell you a story.
My dad always told me two things about fighting: 1. Be careful, because there's always someone bigger and tougher than you. 2. Don't go punching a guy in the head because they could fall, hit their head and die. Then you'd be had up for murder, he always said.
On that last bit he was wrong. No one has been had up for murder after a king-hit in New Zealand.
But there is very little deterrent to king-hits in New Zealand. The sentences we hand out are pathetic and weak, and do not in any way value the life that was lost.
Tarun Asthana was 25 when he was king-hit outside McDonald's in Auckland in November 2013. His killer was naval rating Grenville McFarland. He was sentenced to two years and four months.
McFarland will be out now as a free man, living his new life and he's barely 30.
Yet Mr Asthana lost his life to one punch. His head hit the pavement and he was knocked unconscious, bleeding from the nose and ear. He never regained consciousness and died three days later.
His killer did just over two years inside jail for this. I would be furious. I would be campaigning for change.
And Matthew Coley's killer, Tyrone Palmer, got just 22 months after punching him once in the head in April on the streets of Invercargill.
Palmer was just 16 years old. He was a boy throwing a grown man's punch.
So should we increase sentences to act as a deterrent? To me, it feels right. Surely we need to send a message to society that one punch can kill and there's a price we must pay for that.
Let's rename it the "coward's punch" and let's create more deterrents in the law. Right now it all seems insufficient to me.
But I could be wrong, and experts across the Tasman would say I am. In Australia, lawyers have called for mandatory minimum sentences for "one-punch" homicides to be scrapped, saying they do not prevent violent crime and also can have unjust outcomes.
New South Wales and Victoria both introduced mandatory minimum prison terms for causing death with a single strike in 2014.
The Law Council in Australia wants the mandatory sentences repealed. It claims sending these one-punch killers to jail for longer periods is a terrific way to increase the chance of that person engaging in more serious criminal acts down the track.
So if longer sentences are not the answer, then what must we do?
There are two common threads to me - booze and young men not thinking. King-hit implies someone is a hero. Coward's punch implies someone is a cowardly fool. No man wants to be labelled a coward. I like the idea of it officially being called a "coward's punch" under any sentencing law.
But we must do more than just increase sentences. As parents, we need to warn our children about the risk of booze and bravado. This usually always starts with booze.
Social justice advocate the late Celia Lashlie used to tell us that young boys and young men make silly decisions in their "moment of madness". Sometimes a silly decision made in a split second can affect their life ahead.
Let's do more to teach our young boys right from wrong. Let's do more to teach them about consequence. Let's keep telling our boys what my dad told me - one punch can kill and you could be had up for murder.
It still rings in my ears. It's our job to warn, to caution and to teach boundaries. Let's get on with it.
So, in saying all that, should sentences be longer for someone who throws a cowardly punch and kills? All my instincts still say yes, they should be.