[Dale] made dinner reservations for his sister [Amy]. [Clarence] went to pick up his son [Dale] from the baseball practice.
('Clarence', 'Amy')
[Clarence] went to pick up his son [Dale] from the baseball practice. [Dale] made dinner reservations for his sister [Amy].
[{('Clarence', 'daughter', 'Amy'): [('Clarence', 'son', 'Dale'), ('Dale', 'sister', 'Amy')]}]
['son', 'sister']