then signing his first big contract with the Royals and marrying his sweetheart Yvonne Crittinden within several months, he blossomed into a calm, content young man. His U.S. Olympic teammate Jerry West remarked amicably how much Robertson had "grown up" in that year.[17] In the following years, Robertson fathered daughters Shane Yvonne (b. 1962) and Tia Elaine (b. 1964), and led a private life without scandal; when a biography was going to be written about him in the 1990s, Robertson joked that his life had been "dull", and that he had been "married to the same woman for a long time"[17] However, Robertson proved his character strength in 1997 when his daughter Tia suffered lupus-related kidney failure, and Robertson donated one of his own kidneys.[17] He has been an honorary spokesman for the National Kidney Foundation ever since. In 2003, he published his own biography, The Big O, after his own nickname.