[Antonio]'s brother, [Pedro] went sailing with his other brother, [Robert]. [Robert]'s son [Ronald] is in the hospital. [Ronald]'s brother [Allan] accidentally hit him with a hammer.
('Antonio', 'Allan')
[Antonio]'s brother, [Pedro] went sailing with his other brother, [Robert]. [Robert]'s son [Ronald] is in the hospital. [Ronald]'s brother [Allan] accidentally hit him with a hammer.
[{('Antonio', 'nephew', 'Allan'): [('Antonio', 'brother', 'Robert'), ('Robert', 'son', 'Allan')]}, {('Antonio', 'brother', 'Robert'): [('Antonio', 'brother', 'Pedro'), ('Pedro', 'brother', 'Robert')]}, {('Robert', 'son', 'Allan'): [('Robert', 'son', 'Ronald'), ('Ronald', 'brother', 'Allan')]}]
['brother', 'brother', 'son', 'brother']