[Joshua] took his son [Joseph] out for ice cream. [Joshua]'s son [Clarence], was still in school. [James] is a man with a grandson named [Joseph].
('Clarence', 'James')
[Joshua] took his son [Joseph] out for ice cream. [Joshua]'s son [Clarence], was still in school. [James] is a man with a grandson named [Joseph].
[{('Clarence', 'grandfather', 'James'): [('Clarence', 'father', 'Joshua'), ('Joshua', 'father', 'James')]}, {('Joshua', 'father', 'James'): [('Joshua', 'son', 'Joseph'), ('Joseph', 'grandfather', 'James')]}]
['father', 'son', 'grandfather']