My husband's ancestors came from Scotland to Ireland to Somerset and Cecil counties in Maryland before the 1700's. There were seven brothers-William, 1646-Andrew, 1648-James, 1652-Francis, 1654-Samuel, 1657-Joseph, 1660-John, 1662.Andrew's son, Elias, married Joseph's daugther, Sophia. My husband, William Leslie Alexander is a descendant of this union. The information I found says that it was thought that Reverend James Alexander, of Raphoe was the father of the seven brothers. Rev. James Alexander died in 1704, according to Records of the Synod of Ulster. Contact me if you think there is any connection to your Joseph Alexander.