Michael was born in Chicago, Illinois, on September 12, 1944. He was the son of Pasquale Spilotro, Sr. (1899–1954), a restaurant owner, and his wife, Antoinette. Michael had five brothers, Vincent, Victor, Pasquale "Pat," Jr., Tony and John. He stood at 5' 6" and no one ever called him "Mike" only "Michael". He attended Burbank Elementary School, and entered Charles P. Steinmetz Academic Centre in 1953 with his brothers Victor, Vincent, Anthony and Pasquale. In 1954, Pasquale, Sr. suffered a fatal aneurysm and died at the age of fifty-five.