[Robert] bought an expensive ring for his wife [Marie]. [Marie] took her son [John] to the park for the afternoon. [Pedro] took his nephew [John] to the park to teach him how to ride a bike. [Pedro] 'son [James] could not believe that his father bought him a coffee machine for his birthday.
('Robert', 'James')
[Robert] bought an expensive ring for his wife [Marie]. [Marie] took her son [John] to the park for the afternoon. [Pedro] took his nephew [John] to the park to teach him how to ride a bike. [Pedro] 'son [James] could not believe that his father bought him a coffee machine for his birthday.
[{('Robert', 'nephew', 'James'): [('Robert', 'brother', 'Pedro'), ('Pedro', 'son', 'James')]}, {('Robert', 'brother', 'Pedro'): [('Robert', 'son', 'John'), ('John', 'uncle', 'Pedro')]}, {('Robert', 'son', 'John'): [('Robert', 'wife', 'Marie'), ('Marie', 'son', 'John')]}]
['wife', 'son', 'uncle', 'son']