[Theresa] needed to go to the store. [Theresa] asked her sister [Lillian] for a ride. [Lillian] and her sister [Amy] braided each other's hair before school.
('Amy', 'Theresa')
[Lillian] and her sister [Amy] braided each other's hair before school. [Theresa] needed to go to the store. [Theresa] asked her sister [Lillian] for a ride.
[{('Amy', 'sister', 'Theresa'): [('Amy', 'sister', 'Lillian'), ('Lillian', 'sister', 'Theresa')]}]
['sister', 'sister']