John Parker - How can Nathaniel Parker born 1709, Aaron Parker born 1724, Elizabeth Parker born 1728, Robert Parker, Richard Parker born 1745 and Catharine Parker born 1735 be children of John Parker born 1680 and his wife Martha Tandy?

Geni has two Nathaniel Parker’s 1730 and 1724 as the sons of Nathaniel Parker born 1709 who is alleged as the son of John Parker and his wife Martha Tandy. The Nathaniel Parker 1724-1811 and his father John Parker who died in 1760 Hampshire Count, VA. belongs to Parker yDNA Family Group #18, while the Nathaniel Parker born abt. 1730 (if he’s the alleged father of the Elder John Parker) belongs to Parker yDNA Family Group #5. Only 5 of 25 yDNA markers match between FG# 5 and FG# 18. In order for these to be the same family at least 23 of 25 markers need to match. As to the multiple Nathaniel Parker’s in Hampshire County, VA. see my research on them here: http://freepages.family.rootsweb.ancestry.com/~theduffypapers/parke...
The alleged grandfather of the two Nathaniel Parker’s, John Parker in Geni’s profile who married Martha Tandy died before 9 October 1812 Essex County, VA. (formerly Old Rappahannock County, VA.) when his will was probated by his wife Martha who secured Letters of Administration of his estate [Essex Co. Order Book 1708-1714, 9 October 1712]. The Essex County, VA. John Parker who died in 1712, was the son of the Robert Parker who died 1687 Sittenburne Parish, Old Rappahannock, VA..
If John Parker was born in 1680 Old Rappahannock County, VA. and died in 1812 Essex County, VA., then how could the following as listed by Geni.com: Aaron Parker born about 1724, Elizabeth Nalle born about 1728, Catherine Foreman born abt. 1735, Robert Parker with an estimated birth between 1705 and 1759 and Richard Parker with a birth date listed of 1745 be the children of John Parker of Essex County, VA and grandchildren of Robert Parker of Old Rappahannock County, VA.?.
Catharine (Parker) Foreman’s 1765 Hampshire County, VA. deed of partition is the source that shows that Nathaniel Parker born 1724 (married Elizabeth Scott), Elizabeth Parker (married John Nalle, Aaron Parker (married Mary ‘Molly’ Dobson), Robert Parker (married Hannah Peters), Richard Parker (married Mary Grissel Nalle), and Catharine Parker (married William Foreman) were siblings, and the children of the John Parker who died in 1760 Hampshire County, VA. Most trees that list the children of these siblings show their children (and grandchildren of the John Parker who died in 1760 Hampshire County, VA.) being born from the mid-1750’s through the mid 1780’s.
There are at least two and possibly three different and distinct Parker lines mixed up in these Geni profiles linked to Hampshire County, VA. Oral tradition for the Nathaniel Parker (1724-1811) state that his father John Parker (abt. 1700-1760) migrated to Virginia from Pennsylvania not Essex County, VA / Old Rappahannock County, VA.. See Possible Origins of John Parker ( http://freepages.family.rootsweb.ancestry.com/~theduffypapers/parke... )
Research on John Parker who died in 1712 Essex County, VA by Jean Suddarth as listed on ParkerHannah.com web site (1st KUDZU: http://parkerhannah.com/ParkerParker/JohnPARKER.html ) and on the Parker Heritage web forum. ( https://parkerheritage.ning.com/members/JeanSuddarth/content?type=B... )