[Nicholas]'s son is [Dennis]. [Dennis] and his father always go fishing together on Sundays and have a great time together. [Dennis] took his wife [Emily] out on a date last weekend.
('Nicholas', 'Emily')
[Nicholas]'s son is [Dennis]. [Dennis] and his father always go fishing together on Sundays and have a great time together. [Dennis] took his wife [Emily] out on a date last weekend.
[{('Nicholas', 'daughter-in-law', 'Emily'): [('Nicholas', 'son', 'Dennis'), ('Dennis', 'wife', 'Emily')]}]
['son', 'wife']