[Nancy] took her sister [Lillian] out for dinner to celebrate her birthday. [Nancy] has a son named [Jacob].
('Lillian', 'Jacob')
[Nancy] took her sister [Lillian] out for dinner to celebrate her birthday. [Nancy] has a son named [Jacob].
[{('Lillian', 'nephew', 'Jacob'): [('Lillian', 'sister', 'Nancy'), ('Nancy', 'son', 'Jacob')]}]
['sister', 'son']