[Tina] and her two sisters, [Mildred] and [Pamela], went to visit [Tina]'s brother [Irvin] in Ohio last weekend and had a good time.
('Irvin', 'Mildred')
[Tina] and her two sisters, [Mildred] and [Pamela], went to visit [Tina]'s brother [Irvin] in Ohio last weekend and had a good time.
[{('Irvin', 'sister', 'Mildred'): [('Irvin', 'sister', 'Pamela'), ('Pamela', 'sister', 'Mildred')]}, {('Pamela', 'sister', 'Mildred'): [('Pamela', 'sister', 'Tina'), ('Tina', 'sister', 'Mildred')]}]
['sister', 'sister', 'sister']