[Amy] sat anxiously in the airport terminal, waiting to see her son [Dennis] walk through the gate. [Dennis]'s grandfather, [Clarence], was a world war II veteran.
('Amy', 'Clarence')
[Amy] sat anxiously in the airport terminal, waiting to see her son [Dennis] walk through the gate. [Dennis]'s grandfather, [Clarence], was a world war II veteran.
[{('Amy', 'father', 'Clarence'): [('Amy', 'son', 'Dennis'), ('Dennis', 'grandfather', 'Clarence')]}]
['son', 'grandfather']