Describe the difference between the motivation for Amir leaving money under Hassan's mattress as a child and leaving it under Farid's family's mattress as an adult.

The difference between Amir leaving money first under Hassan's mattress and then under Farid's family's mattress revolves around his motivation. His motivation as a child was to relieve himself of guilt; however, in the case of Farid's family, Amir wanted to help the very needy family.