[Hugh] and his wife [David] made promise to help their son [Brandon]. [Brandon]'s brother [Bobby] is willing to help to.
('David', 'Bobby')
[Hugh] and his wife [David] made promise to help their son [Brandon]. [Brandon]'s brother [Bobby] is willing to help to.
[{('David', 'son', 'Bobby'): [('David', 'son', 'Brandon'), ('Brandon', 'brother', 'Bobby')]}, {('Brandon', 'brother', 'Bobby'): [('Brandon', 'father', 'Hugh'), ('Hugh', 'son', 'Bobby')]}]
['son', 'father', 'son']