Mary Rose O'Neill (born 1935) (b. 1935) Parents Clare Désirée Blow Phelim O’Neill, 2nd Baron Rathcavan Children Barnaby Stewart Hugh Blacker Rohan David Peel Blacker William O’Neill Blacker Siblings Kathleen Mary Starkey Hugh Detmar Torrens O'Neill, 3rd Baron Rathcavan Grania Elizabeth O'Neill Rosetta Anne O'Neill Kathleen O'Neill Moira Louisa O'Neill Partners David Stewart Wellesley Blacker