[Louis] and his brother [Antonio] played at jacks. [Louis] is a great uncle of [Lizzie]. [Robert] and his brother [Pedro] watch [Robert]'s daughter [Lizzie] in her school play.
('Pedro', 'Antonio')
[Robert] and his brother [Pedro] watch [Robert]'s daughter [Lizzie] in her school play. [Louis] is a great uncle of [Lizzie]. [Louis] and his brother [Antonio] played at jacks.
[{('Pedro', 'brother', 'Antonio'): [('Pedro', 'brother', 'Robert'), ('Robert', 'brother', 'Antonio')]}, {('Robert', 'brother', 'Antonio'): [('Robert', 'brother', 'Louis'), ('Louis', 'brother', 'Antonio')]}, {('Robert', 'brother', 'Louis'): [('Robert', 'daughter', 'Lizzie'), ('Lizzie', 'uncle', 'Louis')]}]
['brother', 'daughter', 'uncle', 'brother']