Catherine Blennerhassett Peerage person ID=122009 Parents Conway Blennerhassett Elizabeth Lacy Children Margaret Agnew Blennerhassett James Agnew, 4th of Howlish Hall Siblings Elizabeth Blennerhassett Margaret Blennerhassett Susan Blennerhassett Harman Blennerhassett Anne Blennerhassett John Blennerhassett Thomas Blennerhassett Avice Blennerhassett Partners Robert Agnew, 3rd of Howlish Hall