Lady Henrietta Douglas (1657-1736) (1657–1736) Parents James Douglas, 2nd Earl of Queensberry Lady Margaret Stewart Children James Grierson unknown child Grierson Sir William Grierson, 2nd Baronet Sir Gilbert Grierson of Lag, 4th Bt. Henrietta Grierson John Grierson Siblings Lady Margaret Douglas John Douglas Lady Margaret Douglas Lady Catherine Douglas William Douglas, 1st Duke of Queensberry Lady Mary Douglas James Douglas Lady Isabel Douglas Robert Douglas Partners Sir Robert Grierson, 1st Baronet