[Lena] and her sister [Hugh] went to the ice cream shop. [Lena] went out to dinner with her sister [Cindy], and [Cindy]'s daughter [Wilhelmina].
('Hugh', 'Wilhelmina')
[Lena] and her sister [Hugh] went to the ice cream shop. [Lena] went out to dinner with her sister [Cindy], and [Cindy]'s daughter [Wilhelmina].
[{('Hugh', 'niece', 'Wilhelmina'): [('Hugh', 'sister', 'Cindy'), ('Cindy', 'daughter', 'Wilhelmina')]}, {('Hugh', 'sister', 'Cindy'): [('Hugh', 'sister', 'Lena'), ('Lena', 'sister', 'Cindy')]}]
['sister', 'sister', 'daughter']