John St. Clair of Herdmanston Peerage person ID=577224 Parents William St Clair, 6th Lord Herdmanston Margaret Sinclair Sir John St. Clair of Herdmanston Children William Sinclair of Herdmanston Siblings Margaret Stewart, Countess of Angus Sir Walter St. Clair Elizabeth Stewart Thomas Stewart, 3rd Earl of Angus James St. Clair Partners Elizabeth Polwarth