What does Gregor's father reveal about the families financial status ? What is gregors reaction when he learns the truth ?

From listening to conversations, Gregor discovers that his family doesn't eat much. His father explained the financial situation to the family, and would occasionally use money he had saved from his old business, which had collapsed. Gregor had not known about this money. When his father's business has fallen apart, he had thrown himself into his work and advanced in his job so as to be able to provide for his family. He remembers those times happily, but also recalls that after the initial happiness, the family became used to having him provide for them. He retained a strong bond only with his sister, and wanted to use the money he made to send her to the Conservatory to study the violin.