[Amy] and her sister [Lillian] were getting together this weekend so that they could go hiking together they had n't spent time together alone in a while. [Lillian] and her brother [Dale] went to the movies together.
('Dale', 'Amy')
[Lillian] and her brother [Dale] went to the movies together. [Amy] and her sister [Lillian] were getting together this weekend so that they could go hiking together they had n't spent time together alone in a while.
[{('Dale', 'sister', 'Amy'): [('Dale', 'sister', 'Lillian'), ('Lillian', 'sister', 'Amy')]}]
['sister', 'sister']