As noted, Daniel was a son of Edward Jackson and Lucy Parrish. He may have been the oldest living son. Per the estate docs, his wife was named Sally (lnu) and it is not known if she was his only wife.
The best record that proves the five sons of Daniel is the following land plat that can be found in Daniel's estate administration files located at the Georgia Archives. This plat matches the shape of the original 1784 land grant for Daniel in Crumpton's book. [1]

Estate record for Daniel Jackson indicating 300 acres
51 acres to each of his children and 46 acres that he presumably sold to John Dilcote (Derricott?)
(GA Archives)
This record shows a tract of land divided into 5 equal portions each measuring 51 acres. The names shown are Robert, Joshua, Daniel, John and William who are the sons of Daniel. Son Robert Jackson and Jeremiah Reeves were Executors. Note that Sanders Walker is noted as the surveyor - Sanders was also the man whom Daniel assigned a portion of his Revolutionary War pay. See docs HERE. Jeremiah Reeves was a Baptist Preacher and his namesake son was the pastor of the Sardis Baptist Church in Rayle, Wilkes County, GA. Son John Jackson was a minor at the time of Daniel's death and Thomas Hammock was appointed as his guardian but later John requested Jeremiah Reeves to be his guardian. The last name on the plat is likely John Darracott/Derracott although the spelling may be Dilacote? Daniel may have sold this part of his estate before his death.
In addition to the five sons shown on the plat, Daniel also had a daughter named Sarah who appears to have remained a spinster.

Daniel Jackson's 300 acre plat in Wilkes County, GA
(Bing maps; Annotation by the author)
(GA Archives)
So, we have the following known children of Daniel Jackson and Sally (lnu):
- Robert Jackson - Robert's name can be found on numerous early Wilkes County records. He may have been a Justice of the Peace. He was the administrator of his father's estate.
One very interesting document that contains Robert's name as a witness is the Will of Phoebe Talbot. Phoebe was the wife of John Williston Talbot.[2] It was John Talbot's Wilkes County home where one of the first cotton gins was perfected by Eli Whitney. Also, John and Phoebe had a daughter named Phoebe who married Colonel David Creswell who the son of Rev. James Creswell and Mary Elizabeth Garlington. Mary Garlington was descended from the famous Lancaster County, Virginia Conway and Ball families (Pres. George Washington and Pres. James Madison also descend from these families). This Will of Phoebe Talbot would therefore be a significant historical document. - Joshua Jackson - married Eleanor Wise, daughter of Sherwood Wise. Joshua died about 1829 in Wilkes County, GA. His estate file can be found at the GA. Archives. There is a document in this file that clearly indicates the names the children of Daniel Jackson, Sr. and also the name of Daniel's wife (Sally).
- Harris C. Jackson [3] - married Elizabeth R. Pullin on Apr. 17, 1828 and then married Delilah M. Owen on Feb. 2, 1830. He was appointed the temporary administrator of his father's estate. He was appointed guardian of his sister Mary Ann.
- Irwin Jackson - married Eliza Norman
- Johnson N. Jackson (1855-1935)
- Mary Ann Jackson - is this the Martha A. Jackson living in the household of Joseph Hale Talbot and Bethany Callaway on the 1850 census? See above.
- Lucy Jane Jackson - married John R. Talbot the son of Joseph Hale Talbot and Bethany Callaway
- Saunders W. Talbot (1837-1862) Confederate soldier, died of measles during the Civil War while with Co. J, 37th AL Volunteers
- Luke Turner Talbot (1840-1912) Confederate soldier, Co. I, 37th AL Volunteers, married Sara J. Armor
- Lena Corrine Talbot (1877-1961) married Joseph Wheeler Pepper
- Senator Claude Denson Pepper (1900-1989) Florida Senator and Congressmen.
- Daniel Jackson, Jr. - married Sarah Favor. (Sarah was probably the daughter of John Favor and Mary Bolton). Daniel, Jr. died in 1828 in Wilkes County, GA.
- Mathew F. Jackson (b.1810) married Exey Sims on Aug. 30, 1839
- Richard M. Jackson (1841-1908) married Katherine Morton. Civil War veteran.
- John M. Jackson (b.1846-?) KIA, Civil War
- Anne E. Jackson (b.1847)
- Andrew J. Jackson (1849-1925)
- William Jackson (b.1851)
- Beatrice Jackson (b.1853)
- Alexander S. Jackson (1856-1940)
- Lucinda Jackson (b.1859)
- John F. Jackson
- Nancy Jackson - married John Short
- John Jackson - probably married Polly Hammock (1st) and then he married Jane Wise. John died about 1818 in Wilkes County, GA. See more on John and Jane HERE. The author's line is through John Jackson and Jane Wise. [4] Jane was the daughter of Sherwood Wise and Sarah Patton. Sherwood was a Revolutionary War soldier. Sherwood's brothers and possibly even his father also served as Patriots or helped the Patriot cause. Sarah appears to be descended from the Patton family of Augusta County, Virginia. [5]
The following 2 records indicate the relationship that existed between Daniel Jackson, his sons Robert and John and the Hammock and Reeves families.
Rev. Jeremiah Reeves guardian for John Jackson and his son Rev. Malachi Reeves provided security along with John Hammock (likely related to John Jackson's 1st wife Polly - brother or father?)
(Early Records of Georgia, Vol. I & II, Wilkes County by Grace Gillam Davidson)
Rev. Jeremiah Reeves, co-executor of Daniel Jackson's estate
(Early Records of Georgia, Vol. I & II, Wilkes County by Grace Gillam Davidson)
1793 Wilkes County Militia Record
Note the names of John & Robert Hammock, James, Philip and John Combs, John Eidson and Thomas Talbot - these are all allied families of the author. Reveires and Smallwoods can be found as close neighbors to the author's Wilkes County families.
(Ancestry.com) - William Jackson - William died about 1791 in Wilkes County, GA. Elender, William, Thomas and Jeremiah Jackson were appointed executors. Mark Jackson is noted. Is it not known if he married and had any descendants.
- Sarah Jackson - nothing is known.
Civil War
Wilkes & Oglethorpe Counties turned out hundreds of soldiers that fought for the Confederacy. With so many of the author's ancestors from these counties, there are of course a substantial number of Jackson ancestors and cousins who participated in that conflict, with many giving their lives to the cause.
- Daniel Jackson had numerous descendants that fought for the Confederacy.
- John Jackson's son Anselm Jackson (the author's 2nd great grandfather) lost 2 sons during the Civil War fighting for the Confederacy: One died at Yorktown early in the war and the other died as a result of wounds received at Gettysburg. Another son (the author's great grandfather) survived the Point Lookout POW Camp.
- John Jackson's son John B. Jackson had son Sherwood Wise Jackson who fought for the Confederacy. The Wise family also had sons that fought for the Confederacy. Interestingly, one of the daughters of Sherwood Wise Jackson was named Zettie Jackson, the same name as the author's Jackson grandmother.
- John Jackson's granddaughter, Almeda Jane Jackson, lost her husband (George W. Williamson) during the Civil War. Their son Woodson Lafayette Williamson was the brother-in-law of Governor Lamartine Griffin Hardman. [6]