Wayne (WayneLII@aol.com) said this about Nathaniel's mother, Catherine Britton:
I think that Catharine's mother was Mary Fountain. I found the baptism for Catharine and it has her birth as April 6, 1757. The church was St. Andrew's Church in Richmond, Staten Island ("Staten Island Church Records," by Tobias Wright, p. 247): born April 6, 1757 - parents Nathaniel Brittain & wife- child-Katharine. She had a brother, Richard: (p. 255): born March 22, 1766 - parents Nathaniel Brittain & Mary his wife- child-Richard.