[Pedro] always go on Saturday to his brother 's house [Robert]. This Saturday [Pedro] took his son [James] with him. [Dorothy] visited her son [James] at college. [Robert] liked to play games with his sister, [Tracy].
('Dorothy', 'Tracy')
[Dorothy] visited her son [James] at college. [Pedro] always go on Saturday to his brother 's house [Robert]. This Saturday [Pedro] took his son [James] with him. [Robert] liked to play games with his sister, [Tracy].
[{('Dorothy', 'sister', 'Tracy'): [('Dorothy', 'brother', 'Robert'), ('Robert', 'sister', 'Tracy')]}, {('Dorothy', 'brother', 'Robert'): [('Dorothy', 'son', 'James'), ('James', 'uncle', 'Robert')]}, {('James', 'uncle', 'Robert'): [('James', 'father', 'Pedro'), ('Pedro', 'brother', 'Robert')]}]
['son', 'father', 'brother', 'sister']