[Pedro] loves to play baseball with his dad, [Harold]. [Tracy] was playing in the sandbox with her brother [Robert]. [Robert] took his daughter [Lizzie] to see her grandfather [Harold] after school yesterday.
('Tracy', 'Pedro')
[Tracy] was playing in the sandbox with her brother [Robert]. [Robert] took his daughter [Lizzie] to see her grandfather [Harold] after school yesterday. [Pedro] loves to play baseball with his dad, [Harold].
[{('Tracy', 'brother', 'Pedro'): [('Tracy', 'brother', 'Robert'), ('Robert', 'brother', 'Pedro')]}, {('Robert', 'brother', 'Pedro'): [('Robert', 'father', 'Harold'), ('Harold', 'son', 'Pedro')]}, {('Robert', 'father', 'Harold'): [('Robert', 'daughter', 'Lizzie'), ('Lizzie', 'grandfather', 'Harold')]}]
['brother', 'daughter', 'grandfather', 'son']