Mr. Huntsman was the sixth of nine children born to Jon Huntsman Sr. and his wife, the former Karen Haight. While still enrolled at the University of Utah after a two-year mission in Japan, he married Ms. Wirthlin, a Brigham Young student who was one of 17 children. Twenty-six years into their marriage, they have eight children from the ages of 11 to 25. Early on, the family decamped to Melbourne, Australia, where Mr. Huntsman helped run a Huntsman chemical plant. From there he spent three years at the company office near Houston before rounding off his education at the Wharton School. “I had just had my third child, which I didn’t realize would be such an anomaly in business school,” he said. After a stint at Deutsche Bank in New York, he returned to his hometown and joined his father in the Huntsman building. In 2015, he took control of the private equity fund that manages much of the family fortune. His siblings added to the family’s clout. The eldest, Jon M. Huntsman Jr., a longtime diplomat who is now ambassador to Russia, served as Utah’s governor from 2005 to 2009 and ran for president in 2012. Peter R. Huntsman, the second-born, leads the Huntsman Corporation. Christena Huntsman Durham is one of Mr. Huntsman’s sisters.