[Tracy]'s father, [Harold], was running late picking up his daughter, [Marie], from school. [Pedro] spent the day with his sister, [Marie], and his daughter [Cheryl].
('Tracy', 'Cheryl')
[Tracy]'s father, [Harold], was running late picking up his daughter, [Marie], from school. [Pedro] spent the day with his sister, [Marie], and his daughter [Cheryl].
[{('Tracy', 'niece', 'Cheryl'): [('Tracy', 'brother', 'Pedro'), ('Pedro', 'daughter', 'Cheryl')]}, {('Tracy', 'brother', 'Pedro'): [('Tracy', 'father', 'Harold'), ('Harold', 'son', 'Pedro')]}, {('Harold', 'son', 'Pedro'): [('Harold', 'daughter', 'Marie'), ('Marie', 'brother', 'Pedro')]}]
['father', 'daughter', 'brother', 'daughter']