What does Franka's brother Fredi represent in the novel, White Rose, Black Forest?

Franka's brother Fredi is a symbol of all the good and innocent people that the Nazis killed during their regime. Fredi was a good and kind person who happened to be disabled. Because he was being cared for in an institution, Hitler and the Nazi government decided that such people were wasting resources and that it was simply easier to kill them and save said resources. Fredi is a symbol of the horrid cruelty of the Nazis and how their actions affected everyday people like Franka and her family.