[Jerry]'s grandfather [Clarence] and brother [John] all went to a hockey game after dinner.
('John', 'Clarence')
[Jerry]'s grandfather [Clarence] and brother [John] all went to a hockey game after dinner.
[{('John', 'grandfather', 'Clarence'): [('John', 'brother', 'Jerry'), ('Jerry', 'grandfather', 'Clarence')]}]
['brother', 'grandfather']