[Dennis] did n't get along very well with his sister [Mary] for some reason. [Amy] took her son [Dennis] to the football game.
('Amy', 'Mary')
[Amy] took her son [Dennis] to the football game. [Dennis] did n't get along very well with his sister [Mary] for some reason.
[{('Amy', 'daughter', 'Mary'): [('Amy', 'son', 'Dennis'), ('Dennis', 'sister', 'Mary')]}]
['son', 'sister']