[Nicholas] bought a book for his son [Glen]. [Michael] and his brother [Glen] wanted to backpack across Europe together once they graduated college.
('Michael', 'Nicholas')
[Michael] and his brother [Glen] wanted to backpack across Europe together once they graduated college. [Nicholas] bought a book for his son [Glen].
[{('Michael', 'father', 'Nicholas'): [('Michael', 'brother', 'Glen'), ('Glen', 'father', 'Nicholas')]}]
['brother', 'father']