Here are some notes I posted to another Querry. Your John just adds more intrique to this family. Chambers are also related to McShan's. If you are interested in sharing info please contact me at RAdams38@aol.com. Francis Father in Law is buried in Jefferson Co. AL.
"I believe I have been looking at this same family as a possible tie to My Ancestor Francis Adams born 1797 or 1800 in SC. In the 1800 Census for york Co. Francis Adams is listed and next to him is a William Adams who could be the father of my Francis. Francis Wife Elizabeth McAshan's (Mcshan) sister Matura Ann McAshan, Married a John Adams (Do not know anything about John)in 1835 in Greene Co Alabama. Francis Married Elizabeth In 1828 in Jefferson Co. AL. In the 1830 Census in Jefferson Co. Alabama is listed Francis Adams living next to his in-laws the Mcshans and Moores, 2 pages away is listed a Hillary Adams also born in South Carolina in 1803. Living next to him is a William Adams who seems to be his father. Hillary was married to a Sally Counts in 1824 in Jefferson Co. Alabama.Elizabeth McAshan's brother William B. McShan married a Malvina c. Huston
I have looked at the other 8 Francis Adams living in SC in 1800 and the only one that seems to fit is the one in York Co. SC.
I'm not sure if any of these people tie together but its certainly seems possible.