Catherine Cochrane English noblewoman (1709–1786) Parents Lady Anne Murray John Cochrane, 4th Earl of Dundonald Children Harriet Stewart Keith Stewart John Stewart, 7th Earl of Galloway George Stewart William Stewart Lady Charlotte Stewart Lady Catherine Stewart Euphemia Stewart Lady Margaret Stewart Susanna Leveson-Gower, Marchioness of Stafford Siblings Susan Lyon, Countess of Strathmore and Kinghorne William Cochrane, 5th Earl of Dundonald Anne Cochrane Partners Alexander Stewart, 6th Earl of Galloway