[Pamela] and her mother [Lena] attended a play at the theater. [Lynn] asked her sister [David] to play with her. [David] did n't want to, she wanted to play with her sister [Lena] instead.
('Lynn', 'Pamela')
[Lynn] asked her sister [David] to play with her. [David] did n't want to, she wanted to play with her sister [Lena] instead. [Pamela] and her mother [Lena] attended a play at the theater.
[{('Lynn', 'niece', 'Pamela'): [('Lynn', 'sister', 'Lena'), ('Lena', 'daughter', 'Pamela')]}, {('Lynn', 'sister', 'Lena'): [('Lynn', 'sister', 'David'), ('David', 'sister', 'Lena')]}]
['sister', 'sister', 'daughter']