I can’t remember exactly how it started. I think we downloaded the free version as a reward, because some of the children on the school bus were playing it.

Nor can I remember when we upgraded from Minecraft Lite to the full-blown, paid-for game (and lost control). But one thing I am sure of is: my boys are OBSESSED.

Not just in a passing phase sort of way, but in a ‘we could play this 24/7 if you’d ONLY let us’ kind of way.

And, little did I know that the gaming phenomenon would lead to this bizarre conversation with the 5-year-old addict the other day.

“ LB, I’ve ordered the cake for your party on Sunday – it’s a Minecraft cake! Look, I’ll show you,” I said, opening up my computer and clicking on the picture, depicting Minecraft Steve, a creeper, a zombie and some squared-headed animals.

I sat back expectantly, feeling sure I’d trumped last year’s Titanic cake, waiting for the best-cake-ever response from my Minecraft-mad youngest.

“Aw, Mum, I wanted Squid on my cake!” he replied. [Squid, I discovered later, is an eight-tentacled creature, with blueish-teal skin and teeth underneath his pixelated head – who knew!]

“Squid, or IBallisticSquid?” Son1 piped up. … [Eh??????]

And, with that, I realised it was time I found out more about their obsession – because, like a typical Minecraft parent, I’ve been worried recently that it might be rotting their still-developing brains.

The picture on the video-game cake – I blame it on LB having an older brother

For those who’ve never come across Minecraft before, it’s relatively simple: the game is set in a virtual world made of cubes of different materials (rock, sand, wood, lava and many more) and the goal is to craft, or build, structures out of these blocks, kind of like digital Lego.

It’s not terribly violent; in ‘survival mode’, you have to catch and slaughter a few animals to get food and the zombies can kill you, but in ‘creative mode’, Minecraft is all about building, exploration, creativity and even working together.

My children are members of a mind-bogglingly large and devoted congregation. The freeform building game has 33 million users, many of whom are youngsters aged between 7 and 15 – mainly boys, who see it as their religion.

I’m assuming my sons are typical here, but if they’re not playing Minecraft, they want to spend an unbelievable amount of time watching YouTube videos of other people playing the game. Minecraft celebrities, such as Stampy Longnose, are well-known in our household, and the boys can link servers to ‘play’ with each other.

Lego-mad from a young age, Son1 was drawn to digital Lego like bees to honey

My sons are clearly addicted, however, and forewarned by a friend at work about the lengths these kids will go to (she discovered her teenager was playing for several hours after everyone had gone to bed), we limit the boys’ screen time, much to their chagrin.

You can imagine my dismay, then, when Son1 had to miss swimming at school recently, and told me he’d spent the time playing Minecraft on the computer.

“Really?” I gulped, slightly stunned by this news and annoyed that the school was feeding his habit.

Until I researched it further and found out that the game is actually being used around the world to educate children on everything from science to city planning. It’s been shown to extend kids’ spatial reasoning and constructing skills; and in Sweden, where the game originates from, a school has even made Minecraft compulsory for its 13-year-old students.

So, I’ve decided to fret less over their obsession and take heart in the fact they’re actually collaborating with each other to build these amazingly imaginative worlds and know far more about servers and networks than me. Obviously it’s everything in moderation, but I’m cheered by the news that Minecraft is more than just another video game. I’m also trying to take more of an interest, even in the geeky Minecraft celebrities.

The trouble is, my boys are now attempting to set me a new technical challenge of brain-bending proportions. “Mum, how can we upload videos of us playing Minecraft onto YouTube?”

Stampy Longnose … Squid … you have a lot to answer for.