[David] and her sister [Lena] are the only children in their family. [Lena] made a pie for her daughter [Mildred]. [Mildred]'s sister [Pamela] really enjoyed it.
('Pamela', 'David')
[Lena] made a pie for her daughter [Mildred]. [Mildred]'s sister [Pamela] really enjoyed it. [David] and her sister [Lena] are the only children in their family.
[{('Pamela', 'aunt', 'David'): [('Pamela', 'mother', 'Lena'), ('Lena', 'sister', 'David')]}, {('Pamela', 'mother', 'Lena'): [('Pamela', 'sister', 'Mildred'), ('Mildred', 'mother', 'Lena')]}]
['sister', 'mother', 'sister']