[Lena] and her daughter [Martha] went shopping together last Monday and they bought new shoes for [Lena]'s kids. [Chris] received a nice gift from his grandfather [James]. [Chris] was so proud he showed it to his mother [Lena].
('Martha', 'James')
[Lena] and her daughter [Martha] went shopping together last Monday and they bought new shoes for [Lena]'s kids. [Chris] received a nice gift from his grandfather [James]. [Chris] was so proud he showed it to his mother [Lena].
[{('Martha', 'grandfather', 'James'): [('Martha', 'mother', 'Lena'), ('Lena', 'father', 'James')]}, {('Lena', 'father', 'James'): [('Lena', 'son', 'Chris'), ('Chris', 'grandfather', 'James')]}]
['mother', 'son', 'grandfather']