To me, this seems a bit odd. Perhaps not that he occasionally speaks to his passed grandparents, but that he is carrying the urn around and "playing with them." This seems a little off. But to be completely honest, my family has never cremated. We have always used burial for all of our relatives, so I am not accustomed to the reasoning, traditions, or sentiments of cremation, so perhaps those who are more accustomed with this method of disposition look at it differently. It doesn't necessarily mean anything is wrong, it may just simply mean the way they make peace and come to terms with their loss is a bit different from coping methods used by others. But from my own completely personal point of view, this behavior does seem odd, and again, perhaps it is merely because the customs and traditions I was brought up in are much different, and therefore, I am just unable to relate.