Kessler was born in New York City to Dr. Ernest Borek and Minuetta Shumiatcher Borek, and grew up in Belmont, Massachusetts. After his parents got divorced and his mother remarried he adopted his step-father's last name. His father was born in Hungary and his mother was born in Russia. He attended Clark University in Worcester, Massachusetts from 1962 to 1964 before embarking on a career in journalism. Kessler is married and has two children.DC Style, March/April 2006, page 150
