Your Sarah HAMMON Chaffin was the d/o of John Hammon Sr. of Russell Co, Va. Despite what you see on the internet, the name of John Sr.'s first wife is not known and sometimes confused with other John Ham(m)on(d)(s).
Sarah and all of her siblings are documented in Russell Co., Va. deeds as being the heirs of John Hammon deceased. He was styled as Senior in Russell Co. records because he had a son named John, who was styled both as John Jr. and John Esquire/Gent. because he was a public official and High Sheriff. John Hamon Jr. was the same as Capt. John Hammon, soldier in the War of 1812. His father was not a Captain. The deed book reference for the heirs of John Hammon deceased is Russell Co., Va. Deed Book 5, p. 468 and dated 13 April 1816.
Sarah and James were married before 13 April 1816. Someone has used the date of the deed as the date Sarah was married but that is incorrect unless they were married on the same day the deed was executed.
John Hammon Senior died between 10 Dec 1813 when he, styled as Senr. and his wife Mary sold land to John Hamon Jr., and 5 Dec. 1815 when John is referred to as deceased in a Russell Co. court road order record (DB5:13 & COB5:262). The year of his death of often misstated and sometimes confused with a completely different John Hammond, single man, who died in 1816.
John Hammon Sr was married was at the time of his death to Mary MacKoy [McCoy], the widow of George MacKoy. They married sometime between 1810 (the year George died) and Dec 10, 1813 when John and Mary sold land to John Hamon Jr. She is clearly documented in Russell Co. records. She and John had no children together.
John Hammon Sr. was born by 1751 at the latest but possibly a year or two earlier. He appears in Charlotte Co., Va. court records as a defendant in 1772 under his own name and therefore not a minor. His eldest daughter Elizabeth was born 14 Oct. 1771. John Sr. is often listed as being born somewhat later than 1751 but that is not the case. His parents Ambrose and Ann(e)Hammon were married as early as 1748, when they, styled as being of St. Margaret's Parish in Caroline Co., Va., sold land in Goochland Co., Va.
Less is known about your Sarah than any of the children of John Hammon Sr.
John's Children (not in order):
Son John Jr (b c1780)was also married to a Mary [Stephens] and that has confused some. He is well-documented as a soldier in the War of 1812. John died in Russell Co. in 1826.
Son Ambrose (b 20 Nov 1773) died in Russell Co. in 1842 and his will is of record. His wife's name was Catherine.
Son Robert (b c1784) removed to Pike Co., Ky., then Greenup Co., ky., and finally settled in Lawrence Co., Ohio. He married Rachel Colley.
Daughter Elizabeth (10/14/1771-1/1/1843) married John Grizzle and remained in Russell Co., Va.
Daughter Rebecca (4/2/1782-12/25/1857) married William Grizzle (bro to John)and remained in Russell Co., Va.
Daughter Jane (1788-1833) married Thomas Francis Jr. and removed to Perry Co., Ky.
Daughter Nancy (c1786-after 1850) married Joel Fields and resided in Russell Co.