[Michael] bought a book for his father [Nicholas]. [Nicholas] took his brother [George] to get lunch at a local diner.
('George', 'Michael')
[Nicholas] took his brother [George] to get lunch at a local diner. [Michael] bought a book for his father [Nicholas].
[{('George', 'nephew', 'Michael'): [('George', 'brother', 'Nicholas'), ('Nicholas', 'son', 'Michael')]}]
['brother', 'son']