At least five members of Shaun Finnerty-Gallagher's family were in the public gallery every day.
Yesterday, Mr Finnerty and about 10 others listened in silence as Thomas Tihema Christie (26) was found guilty of manslaughter and indecent assault.
The jury freed Sonny Avon Rehu (32).
Mr Finnerty, of Dunedin, said the verdicts were what he expected, but certainly not what he wanted for the two men who were initially charged with his son's murder.
On Monday, the charges were downgraded to manslaughter after a ruling by Justice Graham Panckhurst.
Mr Finnerty was driving to Christchurch in February last year to pick up his son, but only got as far as Timaru when he received a call informing him his son was missing from the Child, Youth and Family (CYF) home at which he was living.
He turned around and headed back to Dunedin, knowing there was nothing he could do.
He had not expected the phone call the next day telling him his son had been found dead in a Christchurch park.
Sitting through scientific evidence and some of the statements read out in court was "a bit hard in patches", he said.
His son, who "even when soaking wet was no more than 55kg", had no chance against the 26-year-old, 110kg Christie.
But Finnerty tried to remember his son as more than a victim.
Being in court allowed him to build up a picture of what had happened.
"We took him every day - took his ashes along with us to court."
His son was always a handful, as he had severe ADHD.
But he described him as a "lively" teenager who fell in with the wrong crowd.
He had been placed with CYF because family in Christchurch had found him too much.
"He always just wanted to get out and do things.
"He always thought he knew better than you, but that is like most teenagers these days."
Mr Finnerty said the family would remain in Christchurch for the next few days for a "wee break", but he would return for Christie's sentencing on December 4.
Asked what sentence he hoped Christie would get, he replied: "I would expect he would get a long sentence. He should."
