**(Adding This): Also, keep in mind that if he does not keep up with daily things, such as even getting the mail or the mail is piling up... these are indications he can't cope. Something as simple as getting the mail for example, can be very hard on a grieving person... and they may not even open it or pay their bills or keep up with it. ALSO... mail will still be received, addressed to his wife, for example. And this can be real hard, just seeing it, for the grieving spouse. My Mom for example, even after my Dad died... was still getting mail, addressed to him, in the mail. This can be hard on the person. So, simple things, even the mail, can be a real real difficult thing.
Just be real observant of him... since he is a silent griever. Look out for any signs that he may not be taking care of himself, may not be taking care of his own health, not eating well and healthily, not exercising if he does, not taking an interest in daily living... making sure you look out for signs of depression.... or that he cannot handle it himself. Look out for these signs... these are "silent" symptoms of a person who needs help, but they may not reach out for help.
My Dad, was ill for a long time.. and he eventually died. What helped my Mom, was just having all of us help her with daily things... or going over paperwork that was too much for her to cope with. ALSO she participated in a "grief support group." Which helped her immensely... and she found a lot of friends there... because all of these people were going through similar situations. Keep in mind, that "grief groups" are not only for people who have a partner that has already died... but for anyone who is going through a "grieving" and a "loss" of a relationship/marriage/partner for various reasons. Attending her grief support group... was a REAL important factor, in how well my Mom coped with the enormity of the situation. And even though it has been years ago since my Dad died.... she now participates in the grief group as a facilitator... helping others in that situation. That in itself... helps her, and she feels "happy" helping others.
Perhaps as well, a pet, can also help those who are grieving. Pets often can bring solace and companionship to a person, helping them to process things and even if just to serve as a distraction, and a pet can be immensely comforting. And sometimes, a silent griever who is not real expressive, will often "talk" to their pet... thereby helping them to cope.
Mainly, a grieving person really needs help even with the most simple of daily responsibilities & cleaning & making sure things are refilled or shopping lists made out.. even someone just driving them around to do errands WITH them. It is comforting. Because when someone is "grieving".... even the most simple routine chores and errands can seem just too much and too stressful too. Because... their partner cannot be WITH them to do those things, anymore.
I am so sorry... but really, monitor and observe your Uncle, for any signs of depression or difficulty or stress... because a silent griever will not really reach out, if they are suffering or in trouble.
All the best,
Susan