You see the charge and it doesn't add up: in-game purchases, one after another, sometimes on your saved card. Between the anger over the money and the fright that he didn't grasp what he was doing, you can't tell if it was mischief or more.
The sting in your wallet pushes you to treat it as theft and stage the trial. Stop and separate: there's a real difference between not understanding that money was real and knowing it and hiding it. Games are designed so spending doesn't feel like spending —coins, gems, a button—. Before deciding how big your response should be, understand what really happened.
Tell apart three scenarios that call for different responses: he didn't grasp that those «coins» were real money (very common in the younger ones); he understood, did it anyway on impulse and didn't hide it; or he understood, did it and lied or hid it. The first is a matter of understanding and structure (remove the saved card, set a passcode), not punishment. The third adds the problem of the lie, handled separately. The design of these games —pressure, rewards, one click— pushes even adults to spend; reading it this way moves you from «he's a thief» to «we need to close the gap and teach the value of money».
Don't treat a lapse of understanding as a crime: for a small child those gems weren't real money. Don't leave the card saved without a passcode and then act surprised: the gap in the setup is the adult's responsibility. Don't lump everything into one scolding —the spending, the lie if there was one, the game— because the lesson gets lost. And don't humiliate him: the goal is that he understands the value of money, not that he feels like a thief.
No ranking, on purpose: no two children are alike, and yours isn't even the same as yesterday. Read which one fits your home, today — or combine them.
First of all, remove the saved card, set a passcode on purchases, turn off one-click payment. It's the quickest and most effective thing: change the design instead of trusting a child's willpower against a button built to tempt. Design, not surveillance.
Calmly, make the invisible visible: how much that money is in things he understands, where it comes from, what has to be given up by spending it this way. That gems cost real money isn't obvious at his age. Teaching it —and, if it makes sense, having him help repair it with his allowance or chores— turns the fright into learning.
If on top of it he hid it or lied, that's a separate matter and more important than the money: separate it. «The spending we'll fix; what matters most to me is that you hid it from me.» Work on trust without drowning it in the anger over the money. See «A lie discovered».
Close the technical gap right away —that doesn't wait—. The conversation about the value of money, in the cool, once your anger over the charge has come down. If there's another adult parenting or two homes, check that neither has the card saved without a passcode: the gap only needs to be open on one side. If you agree he repairs part of it, keep it proportional to his age, not a crushing debt.
A charge in the game is almost always resolved at home by closing the gap and teaching the value of money. It's worth looking more closely when the spending is repeated despite the controls, when there's sustained deceit to get money, or when it shows up alongside a hook that displaces sleep, school and friends —there may be a problem of impulsivity or compulsive gaming, not just a slip—. If the pattern of spending and hiding repeats and doesn't ease, school counseling or a professional can help read what's underneath. This is peer commentary, not clinical advice.
Everything in this house is peer commentary and suggestion — it does not replace professional help. It's every mother's and every father's responsibility to notice the situation and to seek it when it can serve. If you need a number, check the directory of helplines by country. The full disclaimer, here.
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