When Raskolnikov (Rask) gets his mother's letter, she explains that her pension is small but may be just enough to help out her son. Next, she tells him that his sister, Dounia, is getting married to a slightly arrogant business man, Pyotr.
Rask despises what's happening to his family. He doesn't take a "big brother" stance, but is simply angry that Pyotr is using the family's poverty to get a "legal concubine". Raskhas a large amount of pride in himself seeing that he won't accept any of Pulcheria's pension and later gives money to other poor people.
He has a alot of pride and doesn't want to be taken care of like a bum at the suffering of his mother and sister.