[Jerry] and his grandfather [Clarence] are going mountain climbing. [Jerry]'s brother [Douglas] is too afraid of heights to tag along.
('Douglas', 'Clarence')
[Jerry] and his grandfather [Clarence] are going mountain climbing. [Jerry]'s brother [Douglas] is too afraid of heights to tag along.
[{('Douglas', 'grandfather', 'Clarence'): [('Douglas', 'brother', 'Jerry'), ('Jerry', 'grandfather', 'Clarence')]}]
['brother', 'grandfather']