I am a descendant of Nathaniel Cannon, whose tombstone is online in the Mount Olive Cemetery in Wilkinson Co., GA. It shows he was born in 1760 and died in 1844. His Rev War pension application filed in Wilkinson Co., GA, is also online and he stated in it that "as best he could recollect, he was born in 1763 in SC." He married Frances Sumner of SC and their first son Wiley Cannon was born in Burke Co., GA, in 1792. In 1805, he drew land in Wilkinson Co., GA, and spent the remander of his life there, raising a large family.
I found another reference to the Will of Robert Cannon in, "Orangeburg Dist., SC, Returns in Partition from Court of Equity 1824-1837," by Brent Holcomb, pg. 52-53. In the case of Wolfe & Wife vs. Cannon & Others, in Equity, 1829, it seems that Eleanor Cannon was deceased without a Will, but they were dealing with a couple of gift deeds she had made. Is it possible that the Will of Robert Cannon is filed with these precedings? The SC Archives does not have Robert Cannon's Will online, but they have many other Wills posted.
I am attaching the above reference. On pg. 52 (pg. 76 of the original book), it reads, "It appears by the copy of the last will and testament of the Testator Robert Cannon bearing date 3rd of December 1793 that ...bequeathed as follows: to his widow Elinor Cannon a plantation; also three negroes named Adam, Fan and Rose; and if she should die without making a will the said Negroes to be equally divided between my three children, William Cannon, Rebecca Cannon & Nathaniel Cannon."
On 8 Sep 1824, Eleanor made a gift deed (to be delivered at her death) of 5 slaves to the children of R. Cannon (whom they refer to as her grandchildren).
On 3 Feb 1825, Eleanor made a gift deed (to be delivered at her death) of 3 slaves to her daughter Rebecca Robinson and her heirs.