[Milton] waited patiently on his mother [Amy]. When she did n't show up he called her daughter [Natalia] for help.
('Milton', 'Natalia')
[Milton] waited patiently on his mother [Amy]. When she did n't show up he called her daughter [Natalia] for help.
[{('Milton', 'sister', 'Natalia'): [('Milton', 'mother', 'Amy'), ('Amy', 'daughter', 'Natalia')]}]
['mother', 'daughter']