[Nicholas] and his son, [Dennis], recently heard that [Clarence] was in the hospital. [Dennis] loves his grandfather very much, and went to visit [Clarence] immediately, but [Nicholas] was too busy.
('Nicholas', 'Clarence')
[Nicholas] and his son, [Dennis], recently heard that [Clarence] was in the hospital. [Dennis] loves his grandfather very much, and went to visit [Clarence] immediately, but [Nicholas] was too busy.
[{('Nicholas', 'father', 'Clarence'): [('Nicholas', 'son', 'Dennis'), ('Dennis', 'grandfather', 'Clarence')]}]
['son', 'grandfather']