Leading on from your message re John Adair, son of Rose O'Neal and possible Frazier / Adair connection through wills and neighbours, there may be more about Dr. Alexander Adaire from the historical records of the school named after him ?
Also at :
Maryland State Archives Guide to Special Collections MSA SC 2972-1-45
LEGISLATIVE HISTORY PROJECT Genealogy Collections MSA SC 2972 Dates:1635-1867 Collection Description: Legislative History Project, genealogy charts of legislators and their families. Storage: 02/11/13/01