[John] and his grandfather [Clarence] played a game of chess together. [John]'s sister [Ann] watched and waited to play against the winner.
('Ann', 'Clarence')
[John] and his grandfather [Clarence] played a game of chess together. [John]'s sister [Ann] watched and waited to play against the winner.
[{('Ann', 'grandfather', 'Clarence'): [('Ann', 'brother', 'John'), ('John', 'grandfather', 'Clarence')]}]
['brother', 'grandfather']