[Pedro] has a brother named [Antonio] and a sister named [Marie]. [Pedro] and his brother [Robert] like to go to the movies every weekend. [Dorothy] has started to accompany her brother [Robert] to the movies whenever he goes.
('Dorothy', 'Marie')
[Pedro] and his brother [Robert] like to go to the movies every weekend. [Dorothy] has started to accompany her brother [Robert] to the movies whenever he goes. [Pedro] has a brother named [Antonio] and a sister named [Marie].
[{('Dorothy', 'sister', 'Marie'): [('Dorothy', 'brother', 'Antonio'), ('Antonio', 'sister', 'Marie')]}, {('Dorothy', 'brother', 'Antonio'): [('Dorothy', 'brother', 'Robert'), ('Robert', 'brother', 'Antonio')]}, {('Robert', 'brother', 'Antonio'): [('Robert', 'brother', 'Pedro'), ('Pedro', 'brother', 'Antonio')]}]
['brother', 'brother', 'brother', 'sister']