[George] took his son [John] to batting practice with his baseball team, but had to leave him there alone for an hour to pick up his daughter [Janet].
('Janet', 'John')
[George] took his son [John] to batting practice with his baseball team, but had to leave him there alone for an hour to pick up his daughter [Janet].
[{('Janet', 'brother', 'John'): [('Janet', 'father', 'George'), ('George', 'son', 'John')]}]
['father', 'son']