[Nancy] and her daughter [Linda] went to the park. [Linda] did not invite her brother [Robert] to go to the park.
('Robert', 'Nancy')
[Nancy] and her daughter [Linda] went to the park. [Linda] did not invite her brother [Robert] to go to the park.
[{('Robert', 'mother', 'Nancy'): [('Robert', 'sister', 'Linda'), ('Linda', 'mother', 'Nancy')]}]
['sister', 'mother']