[Natasha] and her brothers, [Richard] and [Leonard], went to visit [Leonard]'s grandmother [Frances].
('Richard', 'Frances')
[Natasha] and her brothers, [Richard] and [Leonard], went to visit [Leonard]'s grandmother [Frances].
[{('Richard', 'grandmother', 'Frances'): [('Richard', 'sister', 'Natasha'), ('Natasha', 'grandmother', 'Frances')]}, {('Natasha', 'grandmother', 'Frances'): [('Natasha', 'brother', 'Leonard'), ('Leonard', 'grandmother', 'Frances')]}]
['sister', 'brother', 'grandmother']