I think it's safe to say that the death of a child is one of the worst things a parent can experience. During this process, there are many different ways that grief can manifest. Ryan Green and his team decided to take their experiences and turn them into a game.
That Dragon, Cancer is a personal story of a man's journey with his young son and their terminal cancer. Playing this game was easily the most emotional I've ever been at E3, and it is one of the most beautiful experiences I've ever gotten to play.
Check out the video for a conversation on the game and creators' philosophy.