[Lillian] went out to dinner with her sister [Nancy], and [Nancy]'s daughter [Linda].
('Lillian', 'Linda')
[Lillian] went out to dinner with her sister [Nancy], and [Nancy]'s daughter [Linda].
[{('Lillian', 'niece', 'Linda'): [('Lillian', 'sister', 'Nancy'), ('Nancy', 'daughter', 'Linda')]}]
['sister', 'daughter']