How does one teach death?

The day my mother died everyone came to the house to apologize and bring food.   It was very different. No one taught me how to handle death (especially a parents death), let alone talking about it with other people. I was 19 but still not old enough to understand care vs social appropriateness. I still remember a time someone failing at making small talk asked me how my day was and I said blankly "ok, my mom died today" it was flat and awkward. I apologized for being so awkward and awkwardly walked away. HA. I can laugh at it because that scare has healed.   But for children who are not 19 and able to see how they are handling the situation is awkward or inappropriate, How do we teach them? I remember at 9 years old and 10 years me grandfather and grandmother passed away respectively. The person who took it the hardest was my 4 year old special needs  cousin. Always asking why are they gone, where did they go, can I see them, when can I see them, where and what and why over and over and over again. I can imagine if he was not a special needs child the answer could be talked about and reasoned with. But my cousin was special needs and his questions just seem to drive the knife deeper that her parents were and are gone. How do you teach him? Hope he forgets his grandparents and he will stop asking? Repeat yourself a 100+ times until you are blue in the face (probably crying by then)? As a child my father always told me whatever I am crying about "it doesn't matter" "stop crying, there are other things to cry about". As I get older and the other things come he now says "these are the things we cry about". How do you present that to a four year old hopped-up on an emotional roller coaster for personal needs? A lot of books talk about having pets in the classroom and when they die... they die. Some even suggest having funerals and keeping pictures of that pet around for memory/conversation starter. But really how do you teach one about death unless they view the way I did. Up close and through a couple years of reflection. Do four year olds really need to be "exposed" the full effect of death or just say "they are gone and we miss them" and move on?