[Clarence] made a sandwich for his son [Wayne]. [Wayne]'s brother [Nicholas] ate an apple instead.
('Clarence', 'Nicholas')
[Clarence] made a sandwich for his son [Wayne]. [Wayne]'s brother [Nicholas] ate an apple instead.
[{('Clarence', 'son', 'Nicholas'): [('Clarence', 'son', 'Wayne'), ('Wayne', 'brother', 'Nicholas')]}]
['son', 'brother']