How do you deal with death...

.....with your child? This is a wrench that was thrown at me today....last year, my son started at a new school, he didn't really know many kids, and most of them already had their friends. My son made some friends, a few, but was bullied a little bit, and did not want to go to school. He would crawl under the covers, cry, and tell me that the lunch lady yelled at him. He made every excuse in the book. It was not an easy year...until, his friend, who was a classroom aid, a young man in his 20's, started playing basketball with him. My son would talk about his new friend, he said that his friend would lift him up so that he could slam dunk, he encouraged him to play flag football this past fall, he even came to a game....today, there was a letter sent home that my son's friend suddenly passed away. WHAT???!!! He was a young guy.....how do I explain this to my son....someone who I know gave my son the confidence to go to school, to play sports, to be a leader, and to participate. He was one of those guys that I know changed my son's life.....I am heartbroken over this loss....I never had the chance to say thank you to him. Never had the chance to say "Thank you so much for helping my son!!!" Thank you so much.....