Bitter water: Conflict erupts between the Cartwrights and the son of one of Ben's closest friends when the son threatens to sell his ranch. Diseased cattle are added to the Cartwright's herd by an unscrupulous land barron bent on destroying the Ponderosa. Known as "Texas Fever," the disease spreads quickly and can wipe out every cattle ranch in the valley. Feet of clay: When young Billy's mother dies and it seems that he has no family, the Cartwrights take him in. The boy insists that his father, who he doesn't know is in prison and will come for him. Hoss, who has taken Billy under his wing, attempts to head off the escaped convict, and in a confrontation, kills him. Now, Hoss must face the boy.