In 2014, Adam Bradford was living an ordinary life in suburban Sheffield, when his father, David, was jailed for two years for stealing £53,000 from his employers to fund a compulsive online gambling habit he’d kept hidden from his family, the news of his downfall splashed across the local paper. “We were devastated because we didn’t know what a gambling addiction really was,” says Adam, 26, co-founder of the Safer Online Gambling Group (SOGG). “In fact we didn’t believe such a thing could exist; we had no awareness of it.”

Slowly, the family started to understand David’s addiction as a psychological problem that needed treatment. But not everyone felt the same. “The news had portrayed our family as ignorant and my dad as a liar and a cheat, and the story about gambling addiction wasn’t being told,” says Adam, whose twin brothers were just 18 at the time. “It was all about criminality, stupidity, carelessness. So we decided to change it.”

Gambling and gaming have been neighbours divided by a brick wall, but now there’s a gateway in it

Within a couple of months he’d begun campaigning for tighter regulation of the gambling industry and action on addiction. Today, Adam and David – who was released on licence after eight months – work together, having created SOGG earlier this year. Last week they launched a campaign tackling the impact on children of what they argue is a link between gambling and gaming created by so-called loot boxes – packs of “in-game” objects, such as new weapons, that players pay to open without knowing what’s inside.

“It’s a game of chance as to whether or not you are going to get a better weapon, or a better player, or extra points,” explains Adam, a social entrepreneur who studied at one of the enterprise academies founded by Dragons’ Den panellist Peter Jones, and won his first award for a small business aged 14. “Odds are not disclosed. That’s why we’re comparing it to gambling.”

That kind of “simulated gambling” normalises betting for children, the group argues, priming them to start doing it formally once they’re old enough. Its survey of 500 mainly game-playing young people aged 11-18 and their parents revealed that adverts for online betting pop up while children played mobile and tablet-based games.

“Gambling and gaming have been neighbours divided by a brick wall, but now there’s a gateway in it,” says David, 63, who was a financial controller before he went to prison. “And I don’t think that gateway is being policed.”

The Bradfords argue there is a link between gambling and gaming created by so-called loot boxes – packs of in-game objects, such as new weapons, that players pay to open without knowing what’s inside. Photograph: Alamy

The stories they heard were “shocking and sad”: a 10-year-old who was in tears explaining how angry and guilty he felt about spending money on something that was worthless once the game was over; an 11-year-old boy playing a simple “brick-breaker” game who’d run up bills of hundreds of pounds on his mother’s credit card he’d taken from her purse, buying coins that allowed him to access new levels.

“His mum was hysterical,” Adam says. “She couldn’t fathom how this so-called innocent game had all these opportunities for a child to spend money to ‘progress’. It’s that linking finance with social success that is very common in gambling. It puts a lot of pressure on kids.”

Half of the young people they interviewed had used a loot box recently, and between them they’d spent an average of £543 a year. Based on Gambling Commission research showing that a third of 11 to 16-year-olds had bought loot boxes, they estimated that children could be spending £250m a year on gaming – using their own money or their parents’. One 16-year-old they encountered had spent £2,000 over three months.

“If you’ve got a family iPad or smartphone, even a video-game console, it’s quite common for a parent to link it to their bank details,” Adam says. Without ID checks on the person playing the game, children can spend that way – and, as some games are classified as suitable for ages three and up, he adds, a very young child could theoretically purchase loot boxes.

The digital, culture, media and sport (DCMS) committee is investigating the links between gaming and gambling and the case for stronger monitoring or regulation of in-game spending. SOGG wants in-game purchasing switched off as a default, and an age-verification system that only allows it to be turned on by over-18s. It’s also calling for the odds for loot boxes to be revealed before they’re bought.

The Bradfords feel they are making progress: they’ve had interest from all the major bookmakers, they say, and are working with Ladbrokes and Coral to design a digital therapy tool.

But what happened to their family is still raw: the hundreds of thousands of pounds of debt David ran up – including remortgaging their house – remain, and he now delivers takeaway food, alongside his voluntary work for SOGG.

“We live with that baggage all the time,” Adam says. Though David says he’s “a million miles” away from gambling again (despite still getting emails with offers from betting companies, whatever he does), Adam and his mother have been taught to remain vigilant, and they control David’s money.

For Adam, campaigning has been a healing process; for David, it’s a way of paying back, and regaining the respect of his family and friends. “Every time there’s a victory, it kind of brings back a reason for living,” he says.