First of all, I thank you for your timely response!
I don't think we link up - at least not until a century or two back in Ireland, I should think. I know very little about my 7-great grandfather, David - only that he was originally from South Carolina, was probably a Tory during the Revolution, and was married to a woman named Ruth (?). He and his family end up in Amite County, Mississippi, and he is dead by 1811. I descend from his daughter, Mary.