It was William John Hobson 1773-1839 (Union Dist. SC Will Book B, p. 620, rec. 28 Oct. 1839), son of Nicholas Hobson and his first wife, Jane [Unknown] who married Cecily Thomas.
William John Hobson was evidently not the son of Sarah "Sally" de Graffenried, who was Nicholas Hobson's second wife (m. ca 1779). This is stated in "de Graffenried Association Newsletter," v. IX, no. 4 (Dec. 1997), errata page 85: "We regret an error was made by the printer when...Volume IX Number 4 was striped-up for printing....but some good came of it. When we were extending the Lunenburg records on page 85, we realized Sarah (de Graffenried) Hobson was not William Hobson's mother."
Although Nicholas and Sarah (de Graffenried) Hobson appear in both of the following volumes, neither William Hobson (1773-1839) nor Cecily (Thomas) Hobson appear in "Baron Christopher de Graffenried V His Ancestors and His Descendants 1191-2005," compiled by Betty Wood Thomas, 2005, nor do they appear in the 1925 de Graffenried history by Thomas P. de Graffenried, "History of the de Graffenried Family from 1191 A.D. to 1925."