Dennis Michael O'Callaghan, 70, of Lowell, Ohio, died Thursday, August 18, 2016, surrounded by his family after a courageous battle with cancer. Dennis was born April 17, 1946 in Cincinnati to immigrant parents, Emma Becker O'Callaghan and Cornelius O'Callaghan. He was co-owner of Gaskets, Packings and Seals in Parkersburg, W.Va. He enjoyed his farm in Lowell, especially riding on his tractor. He was a member of the Vienna Baptist Church. He leaves behind his loving wife, Tammy O'Callaghan (Pauley); his sons, Dennis O'Callaghan Jr. (Mavee), Brandon O'Callaghan, Connor O'Callaghan and Andrew O'Callaghan; his daughters, Kelley O'Callaghan-Connell, Kathleen Crowder (Antwuan), Sydney O'Callaghan, Carly O'Callaghan and Molly O'Callaghan; his sister, Mary Ann Rack; his brother, Terry O'Callaghan and his wife, Kathie O'Callaghan; his grandchildren Chelsea Worley, Torey Worley, Erin Connell, Marissa O'Callaghan and Michael O'Callaghan, Weston O'Callaghan, Jacob Jones and Arionna Crowder. He had one great-grandchild, Melody; and many nieces and nephews. He was loved and respected by many. He will be greatly missed. Friends and family may visit from 3:00 p.m. to 5:00 p.m. Sunday at Vienna Baptist Church, 3401 Grand Central Avenue. A brief service will follow. In lieu of flowers, donations may be made to Women's Care Center of Parkersburg or Strecker Cancer Center in Marietta.