Question: Samuel Robson "Rob" Walton, born on which date, is an American businessman and is the eldest son of Helen Robson Kemper Walton, the wife of Wal-Mart founder Sam Walton, the world's largest retailer?
Sentence (from "S. Robson Walton"): In October 2012, Walton was listed as the 11th richest person in the world.
Relevant evidence: No