[George]'s son [John] entered rehab for the ninth time at the age of thirty. [John] did n't get along very well with his sister [Ann] for some reason.
('George', 'Ann')
[George]'s son [John] entered rehab for the ninth time at the age of thirty. [John] did n't get along very well with his sister [Ann] for some reason.
[{('George', 'daughter', 'Ann'): [('George', 'son', 'John'), ('John', 'sister', 'Ann')]}]
['son', 'sister']