Hannah Lightfoot connection

I've just started doing research on my father's side of the family (Ligon), but I've heard the story of Hannah Lightfoot and King George III since I can remember. From what I've always been told, they had three children, two sons and a daughter (one son sent to Africa, the daughter's whereabouts unknown).  One son, Buxton Lawn, was sent to live with the Lord Mayor of London and he married one of his granddaughters.  Their daughter, Eliza Lawn, married William B. Ligon, and that is the direct link to my family.  If anyone has any other information about Hannah Lightfoot and her daughter, I would be most welcome to receive it!!