Harry and Jen Stables treasure the scrapbooks they lovingly compiled during their grandson Ethan’s childhood.

Flicking through the pages, they pore over pictures that portray an idyllic upbringing in Cumbria, with outdoor adventures, picnics and fancy-dress parties.

One photo after another shows them kayaking, camping, rock-climbing, mountain-biking and feeding farm animals, or Ethan dressed up as pirate Captain Jack Sparrow or Indiana Jones.

‘He was such a bright little boy,’ sighs Jen, 69. ‘As a toddler he could spell out the all the names of dinosaurs in his favourite book.’

Ethan Stables is in jail awaiting sentencing after being found guilty of preparing an act of terrorism, making threats to kill and possessing explosives

Harry, 70, a retired builder who owned his own firm, agrees: ‘He could read my newspaper before he started school. He was a very polite, intelligent, well-spoken boy.’

They imagined one day adding photos of Ethan graduating from university, or standing proud in an Army uniform. But never this. Not the sickening image of their grandson posing in front of a swastika flag.

Today, Ethan Stables, 20, is in prison awaiting sentence for planning a massacre at a Gay Pride event at a pub in Barrow-in-Furness last June.

This month, he was convicted at Leeds Crown Court of preparing an act of terrorism, making threats to kill and possessing explosives.

On his computer, the two-week trial heard, was an ‘awful, disgusting, vile series of posts’ on neo-Nazi chat rooms revealing his ‘deep-seated hatred of black, Jewish, Muslim and especially gay people’.

In his filthy rented flat, police found weapons including an axe, three knives, a machete and a kendo stick (a wooden practice sword), plus materials to make a pipe bomb.

Enraged by a planned LGBT Pride event at the New Empire pub near his home, he had posted footage of himself online burning a rainbow flag and told fellow far-Right extremists he was ‘going to war’.

‘There’s a pride night. I’m going to walk in with a machete and slaughter every single one of them,’ he said in a group message on Facebook. When others tried to dissuade him, Stables replied: ‘I don’t care if I die. I’m fighting for what I believe in and that is the future of my country, my folk, my race.’

Harry and Jen Stables released these pictures of their grandson Ethan. He planned a massacre at a gay pride event

Shocking and despicable as these words were to his grandparents, there was a more personally hurtful revelation to come. Because Stables has since tried to pin the blame for his hateful beliefs on the loving grandparents who helped his single mother to raise him.

Stables has claimed he is bisexual but had repressed his sexuality because his ‘Right-wing’ grandfather would have been ‘disgusted’ with him. This, it was suggested in court, was the reason for his hatred of the gay community.

Married for 48 years, the Stables — a traditional couple who only ever wanted the best for Ethan, whom they describe as a bright but deeply troubled child — look bewildered as they try to make sense of this nightmare.

‘If Ethan had ever said to me he was gay or bisexual, it wouldn’t have bothered me at all. All we’ve ever wanted is for him to be happy,’ says Harry, a catch in his voice.

After their daughter Elaine, a primary school teacher, split from her partner when Ethan was one, the couple couldn’t have been more supportive of them both. Harry was like a father to the boy and cared for him deeply. Seeing him in court, charged with such crimes, was deeply traumatic.

Stables was arrested by armed police as he carried out a final ‘recce’ on the pub, thanks to a 17-year-old girl who reported him after reading his threats.

His defence barrister, Patrick Upward QC, claimed that Stables, who denied all the charges, was a ‘fantasist’ rather than a ‘white supremacist’ — that his threats were the ‘delusional’ rants of an autistic young man.

Stables, who had Asperger’s diagnosed as a child, told the jury he had been ‘brainwashed’ by far-Right friends he had met in internet chat rooms and only made threats ‘to fit in’ and ‘to look big’.

The Stables warn that if this can happen in their safe, loving family, it could happen to others, too. How, they ask, can even the strongest families compete with the internet for influence over their impressionable children?

Evil: Stables posed alongside a Nazi flag. In court he claimed his online threats were attempts to impress other extremists

‘There’s potentially thousands of kids like Ethan out there who now, instead of talking among a group of mates, go on a computer, press buttons and make contacts you don’t know about,’ Harry says.

‘They get themselves into trouble, when this dangerous, hate-filled material shouldn’t be on the internet in the first place.’

Ethan, they say, was more vulnerable than most. His mother described at his trial how her son’s behavioural problems started at the age of two, with extreme temper tantrums during which he would bang his head repeatedly against the floor.

Other parents would reproach her over how ‘naughty’ he was and teachers at his nursery raised concerns. Aged five, Ethan put a plastic bag over his head and told a teacher he wanted to die.

Referred to CAMHS (Child and Adolescent Mental Health Services) aged six, Ethan had Asperger’s — a high-functioning form of autism — diagnosed.

Jen says: ‘Elaine did everything for that boy but she’d often call us sobbing her heart out because his behaviour was uncontrollable. We’d bring him here to give her a break. Even we could see it wasn’t just naughtiness. There was something wrong with him.

‘He was obsessive about washing his hands but refused to dry them, so they were always sore.’

Harry adds: ‘Before Ethan was born, if I saw a kid playing up I’d think “what he needs is a bit of discipline” but that approach just didn’t work with him.

‘I’d ask “what’s wrong, mate?” but he couldn’t articulate his feelings. He had no self-awareness or self-control. It was as if he’d been born with a self-destruct button.

‘On the beach he’d be playing like a happy little boy, then get a handful of sand and throw it in your face for no reason at all... it was as if a switch would turn off in his head. His eyes would go dead and there was no reaching him.’

Corrupted innocence: Before he was a hate-filled neo-Nazi, Ethan Stables was just like any other little boy

For years the Stables fought to get help for Ethan. There were meetings with doctors, psychologists, head teachers and experts, but little real progress.

He remembers one meeting, when Ethan was about 12, when an ‘incisive’ report was produced by his school’s SENCO (Special Educational Needs Co-ordinator).

‘It was spot-on and we thought it was a real breakthrough but there seemed to be no long-term strategy. There was a constant battle at his school over his challenging behaviour.

‘That’s the sad thing, he was so intelligent. It’s heartbreaking. A lot of his frustration came from that — and the older he got, the worse he became. Other children with Asperger’s go on to be successful and with the right help that could have been Ethan, too.

‘Over the years Ethan had sessions with some wonderful medical professionals and would make progress, but then they’d retire or move on and we would be back to square one.

‘Ethan was effectively left to cope on his own, and he just couldn’t.’

The real problems began, Elaine told the jury at his trial, when her son started secondary school.

‘The first term was fine but by the second term it descended into chaos,’ she said. ‘That’s really when he became very oppositional, especially to people in authority.’

He was suspended several times and finally expelled from Furness Academy aged 16, after holding a hacksaw to another pupil’s throat in a fit of temper.

Excluded from mainstream school, Ethan — who claimed he was a victim of bullying — was educated by Home and Hospital Tuition, a council-run service.

With the help of a specialist teacher with experience of autism, Ethan passed several GCSEs. But his teenage years were a time of crisis for the family.

After Elaine met a new partner and married, Harry says Ethan grew resentful of his stepfather. He went to live with his father and stepmother instead, but that arrangement didn’t work out.

He started shoplifting and would go missing. Police became involved. He spoke of carrying out a revenge attack on his old school — and a worried psychiatrist, the court heard, reported him to the police Counter Terrorism Unit in 2015.

Another time he ended up in hospital with a broken arm after falling 30ft from a building, showing off in front of mates as he tried to copy free-runners he had seen online doing death-defying leaps.

Aged 17, he made himself homeless after a row with his mother. Storming to his bedroom, he posted on Facebook that he would chop off his mother’s head, then ‘burn myself and burn the house down’. Jen says: ‘I told Elaine that for her own sanity she couldn’t have him back. She was at the end of her tether.

‘He didn’t want to live with us because our bungalow was too isolated, so he bounced from one place to another.

A selection of potential weapons (right) and a swastika flag (left) were found in Ethan Stables' flat in Barrow, Cumbria

‘One night the council would find him a place in Lancaster, another night in Carlisle, then he found a place in a homeless shelter but they kicked him out, saying he’d ripped a mattress.’

Harry and Jen never gave up on him. They encouraged him when he applied to join the Army at 18 and, after he was rejected, embarked on a land management course, where he did well.

They paid the deposit on the top-floor flat he’d found in a grim mansion block in Barrow, and carted a microwave, bed and furniture up the stairs for him.

After his arrest, it broke their hearts to discover he had been living there in squalor.

Unemployed, he had taken to sitting alone outside the JobCentre for six hours at a time to use the free wi-fi. Surfing the internet, he had come up with one hare-brained scheme after another.

‘One time he wanted to move to Alaska and live wild, another time he wanted to create a small army to free poor black diamond miners,’ says Harry. ‘Then he wanted to fight for IS. He met someone in Germany online, they started talking about Right-wing politics and suddenly that was the answer.’

The court heard Stables became ‘radicalised’ after visiting a girlfriend in Germany. He started searching the internet for information on two extremist groups, Combat 18 and National Action. He viewed terrorism-related videos and investigated how to get hold of guns and how to be declared ‘criminally insane’.

One image found on his mobile phone by police depicted the 2016 massacre of 49 LGBT people at a nightclub in Orlando, Florida, as an arcade shooting game.

Before his arrest, he searched for ‘how to kill a police officer’ and ‘I want to go on a killing spree’. He told others he was ‘just waiting for an excuse to flip’.

The jury decided these were not the empty threats of a harmless fantasist — and judge Peter Collier, QC, adjourning sentence, said that while Stables’ autistic spectrum disorder ‘played a part’ in what he said and did, it did not absolve him of any responsibility.

He told the court he was considering making a hospital order to have Stables detained at a secure mental unit until he was no longer a risk to the public.

For Ethan Stables’s devastated grandparents, this is the outcome they have long dreaded.

‘We can’t say for certain Ethan wouldn’t have harmed anyone. All we can say is that he never had before, save for himself through acts of recklessness,’ says Harry. ‘It’s almost a relief that now he might finally get the help he needs.’