[Lillian] and her sister [Nancy] braided each other's hair before school. [Robert] gave his mother [Nancy] flowers on her birthday.
('Robert', 'Lillian')
[Robert] gave his mother [Nancy] flowers on her birthday. [Lillian] and her sister [Nancy] braided each other's hair before school.
[{('Robert', 'aunt', 'Lillian'): [('Robert', 'mother', 'Nancy'), ('Nancy', 'sister', 'Lillian')]}]
['mother', 'sister']