 At the age of two William's hands and feet became nearly paralyzed, either from polio, or from a doctor administering a dose of calomel (mercurous chloride).Trego's family moved to Detroit in 1874 where William was enrolled in the local school, but an incident where 16-year-old William burned off all his hair with a gas jet made his father decide to teach William in his studio from then on.Despite his crippled hands, young William showed an aptitude for art, learning to paint with a brush jammed in his right hand while he guided it with his left.