Dennis was a graduate of the University of Pennsylvania, Wharton School of Business and retired from Lyondell after serving many years as a business analyst.
Preceded in death by his parents, James and Elizabeth Dunn and brother, Jimmy Dunn. Survived by his daughter, Aleyna Elizabeth Dunn; sisters, Kathy Johnson, Betty Ann Kolb and Mary Theresa "Teese" Shillingford.
Mass of Christian Burial will be held at 10:00 a.m., Saturday, January 5, 2013, St. Theresa Catholic Church, 6622 Haskell, Rev. Phil Lloyd, celebrant. Rite of Committal will follow in Washington Cemetery.