Who was the brother of XXX?
William Temple Thomson Mason
William Temple Thomson Mason was a nephew of George Mason (1725--1792); son of Thomson Mason (1733--1785); half-brother of Stevens Thomson Mason (1760--1803) and John Thomson Mason (1765--1824); first cousin of George Mason V (1753--1796); first cousin once removed of Thomson Francis Mason (1785--1838), George Mason VI (1786--1834), Richard Barnes Mason (1797--1850), and James Murray Mason (1798--1871); uncle of Armistead Thomson Mason (1787--1819), John Thomson Mason (1787--1850), and John Thomson Mason, Jr. (1815--1873); and great uncle of Stevens Thomson Mason (1811--1843).
Stevens Thomson Mason