[Bridget] went to visit her grandfather [Roy] for his birthday. Her sister [Alberta] could n't come as she was busy.
('Alberta', 'Roy')
[Bridget] went to visit her grandfather [Roy] for his birthday. Her sister [Alberta] could n't come as she was busy.
[{('Alberta', 'grandfather', 'Roy'): [('Alberta', 'sister', 'Bridget'), ('Bridget', 'grandfather', 'Roy')]}]