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"): He served as Chairman of Walmart from 1992 to 2015.
Relevant evidence: No