[Lena] liked to play hide and seek with her son [Chris]. [Chris]'s sister, [Martha], bought movie tickets at a discount rate. [Irvin] and his wife, [Martha], went out to the movies for a date.
('Lena', 'Irvin')
[Lena] liked to play hide and seek with her son [Chris]. [Chris]'s sister, [Martha], bought movie tickets at a discount rate. [Irvin] and his wife, [Martha], went out to the movies for a date.
[{('Lena', 'son-in-law', 'Irvin'): [('Lena', 'daughter', 'Martha'), ('Martha', 'husband', 'Irvin')]}, {('Lena', 'daughter', 'Martha'): [('Lena', 'son', 'Chris'), ('Chris', 'sister', 'Martha')]}]
['son', 'sister', 'husband']