[Jacob] and his brother [Jeff] went to the arcade. They had a wonderful time. [Jacob]'s grandfather, [Clarence], took the boy to the store to buy some new shoes.
('Jeff', 'Clarence')
[Jacob] and his brother [Jeff] went to the arcade. They had a wonderful time. [Jacob]'s grandfather, [Clarence], took the boy to the store to buy some new shoes.
[{('Jeff', 'grandfather', 'Clarence'): [('Jeff', 'brother', 'Jacob'), ('Jacob', 'grandfather', 'Clarence')]}]
['brother', 'grandfather']