[Douglas] has an aunt named [Theresa]. [Lillian] and her son [Douglas] went to the zoo and then out to dinner yesterday.
('Lillian', 'Theresa')
[Lillian] and her son [Douglas] went to the zoo and then out to dinner yesterday. [Douglas] has an aunt named [Theresa].
[{('Lillian', 'sister', 'Theresa'): [('Lillian', 'son', 'Douglas'), ('Douglas', 'aunt', 'Theresa')]}]
['son', 'aunt']