[Amy] takes her son [Michael] to the park every Saturday. [Mary] and her brother [Michael] sat down together to clip coupons.
('Amy', 'Mary')
[Amy] takes her son [Michael] to the park every Saturday. [Mary] and her brother [Michael] sat down together to clip coupons.
[{('Amy', 'daughter', 'Mary'): [('Amy', 'son', 'Michael'), ('Michael', 'sister', 'Mary')]}]
['son', 'sister']