Last weekend, [John] went to the beach with his father, [Roy]. They could n't go this weekend, because [Roy] had to go to his daughter [Constance]'s piano recital instead.
('John', 'Constance')
Last weekend, [John] went to the beach with his father, [Roy]. They could n't go this weekend, because [Roy] had to go to his daughter [Constance]'s piano recital instead.
[{('John', 'sister', 'Constance'): [('John', 'father', 'Roy'), ('Roy', 'daughter', 'Constance')]}]