On April 1, 2010, Donovan Smith saw his best friend get stabbed.
• Finding strength to carry on
''You can't really get that image out of your head,'' Mr Smith said in an interview with the Otago Daily Times this week.
In the past four years, many things in Mr Smith's life have changed, but throughout that time, William has never left his thoughts.
Mr Smith, now 20, met William at Waitaki Boys' High School, when they were both year 9 pupils.
''He was my best mate, pretty much since I met him,'' Mr Smith said.
''He was just a fun guy to hang out with ... there was never like a bad moment with him.
''He was always happy, bubbly. He wasn't one to ever get angry, until, obviously, certain events.''
He did not always cover himself in glory, dabbling in drugs and alcohol.
''He was trouble, through and through ... but it was all a bit of fun, just having a good time,'' Mr Smith said.
On the night of his death, the two friends had gone for a walk in central Oamaru.
''We were just laughing, we hadn't been drinking, we were just out having a good night,'' he recalled.
When William heard the rumour that his girlfriend had cheated on him about six months earlier, he was ''gutted'', but he did not get angry until he saw Daniel Smith outside Liquorland that night, Mr Smith said.
He said they had both heard stories of Smith's past ''but I didn't really think about him carrying a knife that night, though; neither did Will, I don't think.''
Mr Smith watched William taunt and push Smith around and accepts he himself was not a peacemaker in the situation.
You could write a novel about his regrets, he said.
''Letting him get out of the car, not pulling him back when I could've,'' he said.
''If I could rewind the clock, I would.''
But he said he never got the impression Smith was scared as William pushed him around, challenging him to a fight.
''[In court] he said he was scared, but his emotions were blank. I've seen fear in people's faces before and it's not what he had on his,'' he said.
Mr Smith said he was ''absolutely convinced'' his best friend was turning to get away from Smith when he was stabbed in the back three times.
''I think had [Smith] said, 'I've got a knife on me, leave me alone', I think Will would've backed off - there wouldn't have been a second thought about it,'' he said.
As his best friend collapsed in a gutter in Exe St, Mr Smith used a T-shirt to try to stop the bleeding from the three stab wounds.
''A lot of things run through your head - the main thing is, I guess, try and save his life,'' he said.
''I knew he was hurt, but I didn't know I couldn't save him.''
Four years later, he still has a vivid memory of events.
''I get my days where it's more than I can handle, but I get past it, I guess,'' he said.
He hoped yesterday's sentencing would give him some closure.
''Every other time, there's the knowing that I've got to go back [to court] and [give evidence] again - this time, I think it's going to give me some closure, that I don't have to keep reliving it.''
But William will never be far from his thoughts.
Mr Smith said he would continue the tradition of gathering with friends and family on William's birthday and on the anniversary of his death to celebrate the life of his ''best mate''.
'It was so scary'
Damian Kovacs saw his mate just 10 minutes before the fatal stabbing.
''He was in a good head space last time I saw him, [he] and Donovan were in good spirits and not out for trouble.''
He recalled William waiting behind a customer when he grabbed an Easter egg and ''jokingly pretended to throw it at the customer''.
The pair wanted Mr Kovacs to join them for a smoke, but as he had to close up the service station he made plans to text them at 10pm, as the pair headed towards Liquorland.
''That was the last time I spoke to him and saw him alive,'' said Mr Kovacs, who was at the sentencing.
''He didn't deserve what happened to him. He was about to get his life on track, do well in his apprenticeship as it meant a lot to him.''
He first saw William in 2008, riding down a hilly Timaru street on a scooter, and ''I thought that was pretty funny''.
''[He] was quite cheeky, and had an awesome sense of humour.
''That's why he got on with everyone he met ...
He was kind, witty; he gave everyone a chance even if he didn't think they deserved it.''
William often spoke of his family, who were in other towns. Once he got his apprenticeship he moved to Oamaru with his then girlfriend, and ''he saw this to be the start of making something of himself and was really stoked about all the changes going on in his life''.
Mr Kovacs said he did not know William's killer but had heard rumours of his reputation.
Falesha Palmer (21), now of Dunedin, was in his same year 10 class at Opihi College, in TemukaShe recalled a typical teenage boy, into food, music and cars, and ''such an easy-going guy''.
"I don't think school was for him, not for me either ... at lunchtimes we used to go have smokes behind the shed. When he moved [to Oamaru] I was sad I didn't see him at school any more.''
She was at a friend's house when she received a text asking if she had heard the news.
''I looked it up on the internet,'' she says, choking back tears.
''Not William ... it was just so scary.''
His death had had a major impact on her.
''That was my first friend when I was 16, and my friend got murdered ... that is a big deal.
''It was a very violent death, and I often think about what it must have been like for him in those last few moments.''
