Upon escorting his 15 year-old son to sectional qualifying, William noticed his son had incorrectly completed his entry form and made him do it again, this time, instructing his son to sign his full name on the entry form because the U.S. Open was the national championship, which demanded a formal name.
Thus, his son signed the form "William Payne Stewart" and a lasting love affair with the U.S. Open began.