[Jerry] wanted to go to the bookstore with his grandfather, [Clarence], but [Jerry]'s brother, [Douglas], told him that [Clarence] wo n't be able to come today.
('Clarence', 'Douglas')
[Jerry] wanted to go to the bookstore with his grandfather, [Clarence], but [Jerry]'s brother, [Douglas], told him that [Clarence] wo n't be able to come today.
[{('Clarence', 'grandson', 'Douglas'): [('Clarence', 'grandson', 'Jerry'), ('Jerry', 'brother', 'Douglas')]}]
['grandson', 'brother']