I think it's important for all of us to understand that even though we shouldn't allow our children near gambling, if a situation like that occurs, you should use your wisdom and handle the situation accordingly. For me, I don't even need to allow my kid to use my KYC information, but all I need to do is take the account or even the device from him, complete the verification myself, withdraw the funds, and then close the account after that. Once I'm done with that, then comes the time when I need to have a talk with him for doing what he shouldn't be doing.
I will first double-think about why he was able to do it in the first place. If I wasn't paying enough attention to him and his activities, and that's why it happened, then I will accept my mistake too, but if he was doing all that by hiding it from me somehow, then it's not my fault, and then maybe I should be a little strict dealing with the situation. However, I believe we should never be too harsh with children, because they can learn and accept better if you teach them with love and affection instead of force and aggression.