My mother and father were both very close to their parents but never raised any sort of memorial to them when they died. My sister says they never even collected their ashes from the crem. We were talking about this last night. She finds it odd. I don't- not particularly. Ashes are only ashes. They're not the person. The person is gone. I have never had the slightest wish to go stand beside my grandparents' (non-existent) graves- and I was very fond of them too. The spirit goes on to other adventures, the person lives in the memory of the living for as long as is appropriate. What more do you need?