What should i do to comfort motherless 8 year old-PLEASE ANSWER?

I think, what you are doing is fine. The cake and stuffed animal is good idea. Another thing to do is invite him to stay with you for the weekend. That will get him away from problems of the family and give him something to think about. You could bake cookies, play outside, or have your parents do something for you guys to do. This would also give his grandma time to get somethings done without the boy around.