I am also seeking information on Charles Harrington; my father WC Harrington, Jr. is the great-great-great-great grandson of Charles via is son William.

My family history document has Charles moving to Cow Island, Louisiana circa 1793; his son William (b 1796); his grandson William (Charles?) (b. 1824); his great grandson Henry Clay (b. 1843); g2 grandson William Owen; g3 William Clayton.

I am seeking more reliable information as well. Have you found any source documents?