[James] took his grandson [Theodore] to the zoo. [Theodore]'s brother [Charles] went to the aquarium instead. [Irvin] and his brother [Charles] went to the arcade. They had a wonderful time.
('James', 'Irvin')
[James] took his grandson [Theodore] to the zoo. [Theodore]'s brother [Charles] went to the aquarium instead. [Irvin] and his brother [Charles] went to the arcade. They had a wonderful time.
[{('James', 'grandson', 'Irvin'): [('James', 'grandson', 'Theodore'), ('Theodore', 'brother', 'Irvin')]}, {('Theodore', 'brother', 'Irvin'): [('Theodore', 'brother', 'Charles'), ('Charles', 'brother', 'Irvin')]}]
['grandson', 'brother', 'brother']