[Theresa]'s son [Travis] and son [Tony] went to the park together to play.
('Travis', 'Tony')
[Theresa]'s son [Travis] and son [Tony] went to the park together to play.
[{('Travis', 'brother', 'Tony'): [('Travis', 'mother', 'Theresa'), ('Theresa', 'son', 'Tony')]}]
['mother', 'son']