Lady Catherine Margaret Powlett,
mother of Lady Augusta Henrietta Vane (b.26th Dec. 1976 d. 11 May 1795)

Augusta married Henry Coore

Lady Catherine Margaret Powlett(born 1766) was the daughter of Admiral Harry Powlett, 6th Duke f Bolton (m. to Katherine Lowther (daughter of Robert Lowther and Catherine Pennington).

She married Sir William Henry Vane, 1st Duke of Cleveland, son of Henry Vane, 2nd Earl of Darlington and Margaret Lowther on 17 September at Hackwood Hampshire England. She died on 17th June 1807 at Cleveland House, St. James's Square, Westminster.

Through her marriage Lady Catherine Margaret Powlett gained the title of Countess of Darlington on 8th September 1792.

Lady St. Helier writes that "she was agreeable, and on the whole, kind, but she was very sarcastic and intolerant; and on the slightest deviation from what she considered the laws of good society, she never scrupled to give her opinion, and that in a very unpleasant manner." Sir Horace Rumbold agreed with this view, writing that she was "kindness itself to those who were so fortunate as to be in her good graces, and the truest and most unflinching of friends."