Hi mum committed suicide and you say he seems to be coping. Tbh he sounds like an absolutely model citizen to me under the circumstances. He's nto out all night or doing drugs. He's obliteratingt he pain via his Xbox. I think I'd do the same.
Please don't give any impression that he is a difficulty or challenge in your life right now. He has exams and his mother killed herself. Can you imagine any more stress on an already hormonal adolescent.
I'd have a good chat with him. Tell him you think that some gaming every day is probably quite a good thing for him (read Superbetter - or watch gamer and author Jane McGonigal talking about the unsiung benefits of gaming) Suggest a generous amount of time =- about two hours. But suggest too that he doesn't do it just before bed, as it might spoil his sleep. Honestly, show interest in his gaming and if you read Superbetter, you can very casually and subtly mention how certain gaming tactics can be applied very successfully to life.
Give him lots of compliments whenever you can. Respect his decisions. E.g. If my son had told me he;d quit his paper round and his dad had killed himself, I;d say: That's fine. Your body is more tired than usual. It;s a normal symptom of stress after your dad's death. You need to reduce the demands on you and that was a really sensible choice. Having a paper round is optional, so dropping out from it makes sense. But preparing for exams is not optional and I realise how hard it must be to concentrate rigth now after all that;s happened. What can I do to help you?
Get involved in his revision. Be strategic. Talk to him about his strongest and weakest subjects. Suggest, if necessary, that he allows himself to flunk one of the weaker ones, so that he can concentrate on good grades in the core five or six. Both English, maths and two or three other subjects that either he finds easier or that might help him move on to what he might want to do later.
Is he getting support from a good bereavement counsellor?
Are you keeping an eye on his diet? At this time of year he could be getting quite depressed anyway. Make him turkey burgers (turkey has a chemical that lifts your mood in it, which is why it;s so popular at this time of year. Buy him some vitamin supplements, especially some Vitamin D spray. Show him you care about him and not that he is an effort to be endured.
Try to do stuff together - watching sport on TV or taking his younger brothers out for a forsty walk somewhere pretty.
It can;t be easy for any of you. I really feel for all of you. My heart goes out to all of your children. And you. What a tough job you have. But long term, you will feel so proud of yourself if you help him through this with love and kindness and attention rather than closing down and judging him.