[Bobby] and his brother [Bernardo] liked to eat pizza but [Bernardo]'s sister [Bettie] liked to eat tacos. [Antonio] took his son [Bobby] out for ice cream. [Antonio]'s son [Aaron], was still in school.
('Aaron', 'Bettie')
[Antonio] took his son [Bobby] out for ice cream. [Antonio]'s son [Aaron], was still in school. [Bobby] and his brother [Bernardo] liked to eat pizza but [Bernardo]'s sister [Bettie] liked to eat tacos.
[{('Aaron', 'sister', 'Bettie'): [('Aaron', 'brother', 'Bobby'), ('Bobby', 'sister', 'Bettie')]}, {('Bobby', 'sister', 'Bettie'): [('Bobby', 'brother', 'Bernardo'), ('Bernardo', 'sister', 'Bettie')]}, {('Aaron', 'brother', 'Bobby'): [('Aaron', 'father', 'Antonio'), ('Antonio', 'son', 'Bobby')]}]
['father', 'son', 'brother', 'sister']