John St Clair, Master of Sinclair British politician (1683–1750) Parents Henry St. Clair, 1st/10th Lord Sinclair Grizel Cockburn Children Siblings James St Clair Henry St. Clair David St. Clair Catherine St. Clair Elizabeth St. Clair Margaret St. Clair William St. Clair Matthew St. Clair Grizel St. Clair unknown daughter St. Clair Partners Lady Margaret Stewart Amelia Murray