 When General Sir William Johnson , Superintendent for Northern Indian Affairs , visited Canajoharie , he always stayed at the house of his friend , Molly 's stepfather Brant Kanagaradunkwa . Johnson and Molly Brant became intimate ; in September 1759 , she gave birth to his son , Peter Warren Johnson , named for Sir William 's early patron and uncle , Admiral Sir Peter Warren . Brant lived with Johnson at Fort Johnson , and then Johnson Hall after 1763 , becoming effectively Sir William 's common @-@ law wife or consort . The couple had nine children together , eight of whom lived past infancy . They included the following : 
