[Beverly] went to the park with her sister [Tracy]. [Tracy] decided not to invite her brother, [Robert], though. [Pedro] went out for pizza with his daughter [Rebecca] and his brother [Robert].
('Beverly', 'Rebecca')
[Beverly] went to the park with her sister [Tracy]. [Tracy] decided not to invite her brother, [Robert], though. [Pedro] went out for pizza with his daughter [Rebecca] and his brother [Robert].
[{('Beverly', 'niece', 'Rebecca'): [('Beverly', 'brother', 'Pedro'), ('Pedro', 'daughter', 'Rebecca')]}, {('Beverly', 'brother', 'Pedro'): [('Beverly', 'brother', 'Robert'), ('Robert', 'brother', 'Pedro')]}, {('Beverly', 'brother', 'Robert'): [('Beverly', 'sister', 'Tracy'), ('Tracy', 'brother', 'Robert')]}]
['sister', 'brother', 'brother', 'daughter']