Ryan Liddell's victim, a 76-year-old retired nurse, described him as a man who looked like the devil.
What the jury in his trial did not hear was that as a five-year-old child, Liddell was one of the survivors of the Dunblane Primary School massacre on 13 March 1996.
The school gym shooting spree by Thomas Hamilton killed 16 Primary One children and their teacher, and left another 12 pupils and two staff wounded.
Liddell's link to the massacre was not revealed in the trial at the High Court in Dumbarton, which ended with him being convicted of assaulting the woman with intent to rape.
However, the jury was told he was diagnosed with attention deficit hyperactive disorder (ADHD) at the age of six and that he had sleeplessness and anxiety since childhood.
Following the massacre at his school during a gym class, Liddell was placed in intensive care at Yorkhill Hospital in Glasgow suffering gunshot wounds.
He was hospitalised for more than a week while he had surgery to repair a collapsed lung and broken right arm.
Five-year-old Ryan was an only child being brought up by his mother Alison Curry. His father had died of meningitis when Liddell was a baby.
Ms Curry, a secondary teacher who had previously worked at Dunblane Primary School as a trainee, was one of the first on the scene after Hamilton appeared in the school gym.
She was in the playground on her way to meet a teacher when the shooting started.
In a newspaper interview a year later, Ms Curry said a man appeared at the gym fire exit, tried to shoot her then went back into the building to kill himself.
It was only when she ran to her son's classroom and saw piles of school uniforms that she realised Ryan had been in the gym.
She later described the attack as an "incomprehensible horror".
In a front page story on 13 March 1997, the anniversary of the killings, The Mirror ran a photo of a smiling six-year-old Ryan with the headline: "His smile is proof that Dunblane can face the future."
Ms Curry told the paper that although her son had healed physically, he still bore mental scars.
"He was frightened at first that the bad man might come back and get him. I had to explain that Thomas Hamilton had killed himself," she said.
"When he heard I was shot at, he had terrible nightmares. Ryan's dad died of meningitis when he was 10 months old. I think he was terrified of losing me too.
"A lot of people assume the injured children are better now, but things can never get back to normal for them."
The survivors were offered support throughout their school lives, including counselling, and psychologists were on hand when they moved up to secondary school in 2002.
However, Liddell continued to lead a troubled life.
The court heard that he had very few friends and lived alone, having fallen out with his mother and stepfather.
Even his own friends described him as "strange" and he described himself as "an idiot" and "naive".
After the verdict Dr Vince Egan, a forensic psychologist at Leicester University, said: "Liddell might have been left distressed and traumatised by the Dunblane massacre, but so would all the others involved, and nobody else has behaved like this.
"It doesn't provide any excuse for what he did to that elderly lady, and post-traumatic stress syndrome isn't going to lead to a reaction like this 15 years on.
"This is certainly the most extreme behaviour I've heard from anyone after a traumatic event."