Complex sentence: Her first cousin was Kingman Brewster, Jr., (June 17,1919--November 8,1988) was an educator, president of Yale University, and the U. S. ambassador to the Court of St. James's from 1977 to 1981.
Split into simpler sentences: Her first cousin was Kingman Brewster, Jr. (June 17,1919--November 8,1988). He was an educator, president of Yale University, and the U. S. ambassador to the Court of St. James's from 1977 to 1981.