Thomas St Lawrence, 3rd Earl of Howth Irish peer (1803–1874) Parents Margaret Burke William St. Lawrence, 2nd Earl of Howth Children Lady Emily St. Lawrence Lady Mary St. Lawrence Lady Catherine St Lawrence Lady Geraldine St. Lawrence Lady Henrietta St Lawrence Margaret Domville William St Lawrence, 4th Earl of Howth Thomas St Lawrence Siblings Lady Catherine St. Lawrence Lady Harriet St. Lawrence Lady Matilda St. Lawrence Lady Isabella St. Lawrence Mary St. Lawrence Partners Henriette Barfoot Lady Emily de Burgh