The Unfortunate Advantage

There is a rich child and a poor child. The rich child invites the poor child to his house and shows him all the toys and tells him: "Look at what a beautiful radio-controlled airplane I have! You don't have it because you are poor!" The poor child answers: "You're right, it's very nice, but I have one thing that you don't have!" The rich child then invites him into the garden and shows him the swimming pool, the trampoline, and all the other games that can be done outdoors and says to the poor child: "Look at that beautiful swimming pool I have! It is very big; you don't have it because you are poor!" And the poor child says: "Beautiful, it is really beautiful! But one thing that you don't have." So the rich child feels bad. He says: "Wait, but I'm rich! How is it possible? I have everything I want because I'm rich. Why do you have something that I don't have?" And the poor child says: "I have cancer!"