Arthur Blennerhassett 19th-century Irish politician (1799–1843) Parents Dorcas Twiss Arthur Blennerhassett Children Adelaide Blennerhassett Henry Deane Blennerhassett Amelia Blennerhassett Frances Annabella Blennerhassett Dorcas Blennerhassett Charles John Allanson Winn Blennerhassett Siblings William Blennerhassett John Blennerhassett Partners Frances Deane O'Grady