I'm confused about the number of men named Richard Bush in Edgefield County, South Carolina in the late eighteenth and early nineteenth centuries.
A Richard Bush was a legatee of the estate of the elder Richard Bush who died in Edgefield in 1803. That makes two Richards. Bibby Bush, who was a co-administrator of the elder Richard's estate, also had a son named Richard. That makes three Richards. Which is one more Richard than can be readily accounted for in the census, land, and estate record.
There were only two Richard Bushes enumerated in the 1790 census of Edgefield (the elder and either his son or Bibby's son), only one in the 1800 census (either the elder's son or Bibby's son because the elder was enumerated with his son John), and none in the 1810 census (the elder was dead and Bibby's son lived in nearby Augusta, Georgia.)
Also, it's not clear from the land record that there were more than two Richard Bushes. From at least 1786 until shortly before his death in 1803, the elder Richard was almost always called Richard Bush Senior in his deed record. From at least 1786 until the elder Richard's death, a younger Richard was almost always called Richard Bush Junior in his deed record. However, there's no way to positively say that the younger Richard was the son of the elder Richard or the son of Bibby. After the death of the elder Richard in 1803 until at least 1828 (the year Bibby's son Richard died) no land record mentions a Richard Bush Junior, as would be expected if there were still two Richards.
Finally, there is no estate record for a Richard Bush in or near Edgefield other than the Richard who died in 1803 and the son of Bibby who died in Augusta, Georgia in 1828.
As I see it, there are four possible solutions to the problem --
1. There were three Richard Bushes, and the extant record is insufficient to clearly distinguish between the son of the elder Richard and the son of Bibby. This would certainly be the case of the son of the elder was still a minor in 1803.
2. There were three Richard Bushes, but the son of the elder Richard was mentally or physically handicapped and had no census, land, or estate record. However, if this is the case then he became incapacitated in or after 1786 or else the Richard Bush Junior who witnessed deeds for the elder Richard that year was the son of Bibby Bush.
3. There were two Richard Bushes and the son of Bibbybecame a legatee of the elder Richard because he was the favorite grandson. Perhaps he was closer to the elder Richard in his old age than were his own sons.
4. There were two Richard Bushes and the son of Bibby married a stepdaughter of the elder Richard and thus became a legatee because he was a son-in-law (as the term was used in colonial days.)