Alice Walton (net worth: $33.7 billion)

Born in 1949, Alice Walton is the youngest child of Wal-Mart founder Sam Walton and the heiress to his fortune of Wal-Mart Stores, Inc. – the world’s biggest retailer and largest employer in the U.S. As an avid art lover, she donated her collection of American art to her museum, Crystal Bridges, in 2011.