What does Amir put under Hassan's mattress? Why does he put these things under Hassan's mattress?

On the one hand, the moral of the bundle of sticks, reflects on the idea that "union makes strength": when each of the sons tried to break the entire bundle of sticks, no one was able to do it. therefore, the dying father tells them: "untie the bundle and each of you take a stick", so the sons were finally able to break the sticks, by breaking them individually, but in the end, through the union of the brother's forces, altogether.on the other hand, the moral of "hofus the stonecutter", refers to how people unecessarily want to be superior in hierarchy in society. the tale shows how a stonecutter always wishes to become someone or something superior than him, for instance, when he sees that the cloud is stronger than the sun (when he was the sun), so he wishes to be "the storm". but in the end, he realizes the stonecutter was the strongest of all.