Not just spoken by the heroine of the novel F.M. Dostoevsky «The Mistress», the words sister, brother are in work to work. The article is devoted to analysis of the idea of kinship to the artistic world of the novel. This idea organizes the plot. Ring composition reflects the loneliness of Ordinov, his verwendest from the family circle. Sisterly-brotherly relations, proposed hero Katerina, do not become the basis for the formation of a true family, but they are given as an ideal norm of human coexistence.