Spencer Mildmay St. John (1822-1849) (1822–1849) Parents Maria St. John-Mildmay Henry St John, 4th Viscount Bolingbroke, 5th Baron St John Children Siblings Anne Jane Charlotte St. John Maria Louisa St. John Henry St John, 5th Viscount Bolingbroke, 6th Viscount St John Emily Arabella Jane St. John Isabella Letitia St. John Partners Dora Clutterbuck