Secondary sources show John's wife as unknown, as Hannah __?__, or as Elizabeth "Betty" JENNINGS.  I have no idea which, if any, is correct.

1.  Marriage Records:

2.  WorldConnect / Ancestry World Trees (online at RootsWeb.com/Ancestry.com).  Files there quote this will:

In the name of God, Amen: I, John Corbin, of King George County being sick and weak but in perfect mind and memory, God be thanked for same, do make and ordain this my last will and testament and for what Temporal estate God has blessed me with I shall depose of in manner and form following: Item: I give to my son Francis Corbin one black mare and one gun. Item: I give to my son David Corbin one feather bed and furniture Item: I give to my Daughters, Alice Corbin, Milla Corbin and Margaret Corbin twenty shillings each. Item: My will and desire is that my land and all my personal Estate (except what is above mentioned) be sold at public auction to the highest bidder and what money is raised from that sale after my Debts, Legacies and funeral expense are paid, to be equally divided amongst all my sons and Daughters, William Corbin, John Corbin, Francis Corbin, David Corbin, Elizabeth Armstrong, Alice Corbin, Milla Corbin and Margaret Corbin. I do appoint my two sons William Corbin and John Corbin to be executors of this my last will and testament. His X mark John Corbin (seal) Seal and delivered in the presence of Anderson Doniphin; William Bruce; William King-  At a court held for King George County the 2nd day of November 1758... the within last will and testament of John Corbin deceased, was presented into Court by John Corbin one of the executors therein named and same was proved by the oaths of William Bruce and Anderson Doniphin two of the witnesses thereto subscribed and ordered to be recorded and is truly recorded.

What is the date the will was signed?