[Chris] and his brother [Charles] were arguing over which show to watch. [Charles] asked his grandmother [Frances] to decide, but [Frances] turned off the TV instead. [Lena] visited her son [Chris] at college.
('Lena', 'Frances')
[Lena] visited her son [Chris] at college. [Chris] and his brother [Charles] were arguing over which show to watch. [Charles] asked his grandmother [Frances] to decide, but [Frances] turned off the TV instead.
[{('Lena', 'mother', 'Frances'): [('Lena', 'son', 'Chris'), ('Chris', 'grandmother', 'Frances')]}, {('Chris', 'grandmother', 'Frances'): [('Chris', 'brother', 'Charles'), ('Charles', 'grandmother', 'Frances')]}]
['son', 'brother', 'grandmother']