[John] often goes out for lunch with his sister, [Michelle]. [Robert] was proud of his son, [John]. [Allan] is a very hot guy, but his sister [Michelle] is even more attractive. [Pedro] and his nephew [Allan] went hunting together last weekend.
('Robert', 'Pedro')
[Robert] was proud of his son, [John]. [John] often goes out for lunch with his sister, [Michelle]. [Allan] is a very hot guy, but his sister [Michelle] is even more attractive. [Pedro] and his nephew [Allan] went hunting together last weekend.
[{('Robert', 'brother', 'Pedro'): [('Robert', 'son', 'Allan'), ('Allan', 'uncle', 'Pedro')]}, {('Robert', 'son', 'Allan'): [('Robert', 'son', 'John'), ('John', 'brother', 'Allan')]}, {('John', 'brother', 'Allan'): [('John', 'sister', 'Michelle'), ('Michelle', 'brother', 'Allan')]}]
['son', 'sister', 'brother', 'uncle']