[Clarence] went bike riding his grandson [James]. [James]'s father [Dale] was skateboarding.
('Dale', 'Clarence')
[Clarence] went bike riding his grandson [James]. [James]'s father [Dale] was skateboarding.
[{('Dale', 'father', 'Clarence'): [('Dale', 'son', 'James'), ('James', 'grandfather', 'Clarence')]}]
['son', 'grandfather']