[Amy] has a son named [Michael]. [Clarence] and his grandson [Michael] love to go to the ball park.
('Amy', 'Clarence')
[Amy] has a son named [Michael]. [Clarence] and his grandson [Michael] love to go to the ball park.
[{('Amy', 'father', 'Clarence'): [('Amy', 'son', 'Michael'), ('Michael', 'grandfather', 'Clarence')]}]
['son', 'grandfather']