You mention that John Hubbard was the husband of SARAH STONE of Caroline County, with a will in Amelia in 1745. She remarried a John Carter who was dead in Caroline County in 1750, with Charles, John, and George Carter being also named.
I do NOT think these are the same people, but the name similarity could cause lots of confusion, so ....for what it is worth, see the reference to Stone at this link in the Arrington forum: http://genforum.genealogy.com/arrington/messages/1463.htmlhttp://genforum.genealogy.com/arrington/messages/1463.html and look at the paragraphs below "Page-224" which reference a "widow Stone" in Halifax County. Richard Stone Arrington in that message was the first husband of Catherine Carter [b. 1 Jan 1766, she later married Abner Farrar and wound up in GA]. Catherine (Carter) (Arrington) Farrar was a younger child of Lucy (Marshall) and her first husband Charles Carter. This was the Charles Carter who was born about 1732 and died about 1771, of Lunenburg and Brunswick Counties. This is the same Charles Carter who in his will mentioned a brother named John, and a nephew named John, and a son Charles [who may not have survived to his majority].