[Robert] took his brother [Pedro] to get lunch at a local diner. [Tracy] took her brother [Robert] and her daughter [Laura] out for dinner at Chili's. [Laura] gave her Aunt [Beverly] a kiss.
('Pedro', 'Beverly')
[Robert] took his brother [Pedro] to get lunch at a local diner. [Tracy] took her brother [Robert] and her daughter [Laura] out for dinner at Chili's. [Laura] gave her Aunt [Beverly] a kiss.
[{('Pedro', 'sister', 'Beverly'): [('Pedro', 'sister', 'Tracy'), ('Tracy', 'sister', 'Beverly')]}, {('Tracy', 'sister', 'Beverly'): [('Tracy', 'daughter', 'Laura'), ('Laura', 'aunt', 'Beverly')]}, {('Pedro', 'sister', 'Tracy'): [('Pedro', 'brother', 'Robert'), ('Robert', 'sister', 'Tracy')]}]
['brother', 'sister', 'daughter', 'aunt']