[Robert] watched his son [Ronald] play catch. [Ronald] tossed the ball back and fourth with his brother [Mario]. [Marie] took her son [Mario] shopping for new school clothes. They had a good time. [Marie] is always around her brother [Pedro].
('Robert', 'Pedro')
[Robert] watched his son [Ronald] play catch. [Ronald] tossed the ball back and fourth with his brother [Mario]. [Marie] took her son [Mario] shopping for new school clothes. They had a good time. [Marie] is always around her brother [Pedro].
[{('Robert', 'brother', 'Pedro'): [('Robert', 'son', 'Mario'), ('Mario', 'uncle', 'Pedro')]}, {('Mario', 'uncle', 'Pedro'): [('Mario', 'mother', 'Marie'), ('Marie', 'brother', 'Pedro')]}, {('Robert', 'son', 'Mario'): [('Robert', 'son', 'Ronald'), ('Ronald', 'brother', 'Mario')]}]
['son', 'brother', 'mother', 'brother']