[Theresa] was unhappy with her son, [Nicolas], and his grades. She enlisted a tutor to help him. [Theresa] took her younger sister [Lillian] to the carnival last weekend.
('Lillian', 'Nicolas')
[Theresa] took her younger sister [Lillian] to the carnival last weekend. [Theresa] was unhappy with her son, [Nicolas], and his grades. She enlisted a tutor to help him.
[{('Lillian', 'nephew', 'Nicolas'): [('Lillian', 'sister', 'Theresa'), ('Theresa', 'son', 'Nicolas')]}]
['sister', 'son']