[Nancy] loves to make cookies for her son. His name is [Robert]. [Nancy] and her sister [Amy] braided each other's hair before school.
('Amy', 'Robert')
[Nancy] and her sister [Amy] braided each other's hair before school. [Nancy] loves to make cookies for her son. His name is [Robert].
[{('Amy', 'nephew', 'Robert'): [('Amy', 'sister', 'Nancy'), ('Nancy', 'son', 'Robert')]}]
['sister', 'son']