[Harold] took his grandson [Bobby] to the baseball game. [Bobby]'s brother [Bernardo] hates baseball. [Tracy]'s son [Aaron] and son [Bernardo] went to the park together to play.
('Aaron', 'Harold')
[Tracy]'s son [Aaron] and son [Bernardo] went to the park together to play. [Harold] took his grandson [Bobby] to the baseball game. [Bobby]'s brother [Bernardo] hates baseball.
[{('Aaron', 'grandfather', 'Harold'): [('Aaron', 'brother', 'Bernardo'), ('Bernardo', 'grandfather', 'Harold')]}, {('Aaron', 'brother', 'Bernardo'): [('Aaron', 'mother', 'Tracy'), ('Tracy', 'son', 'Bernardo')]}, {('Bernardo', 'grandfather', 'Harold'): [('Bernardo', 'brother', 'Bobby'), ('Bobby', 'grandfather', 'Harold')]}]
['mother', 'son', 'brother', 'grandfather']