[Louise] went to the store with her sister [Heidi]. Later that day, [Louise] had tea with her sister [Lorraine].
('Lorraine', 'Heidi')
[Louise] went to the store with her sister [Heidi]. Later that day, [Louise] had tea with her sister [Lorraine].
[{('Lorraine', 'sister', 'Heidi'): [('Lorraine', 'sister', 'Louise'), ('Louise', 'sister', 'Heidi')]}]
['sister', 'sister']