6. Walton Family ($35 billion each)
The Walton children—Christy, Jim, Alice, and S. Robson Walton—inherited their fortune after carrying out a plot to kill their father, Sam Walton, founder of the Wal-Mart and Sam’s Club superstore empire. Having sat down and carefully laid out precisely when and how they would pull their father from his bed, hold him facedown in the bathtub until he stopped fighting, and then dispose of his body, the Walton children were able to take control of the world’s largest retail chain and the billions it is worth.