[Charles] and his sister [Martha] went to visit their grandmother [Frances] and her husband [James]
('James', 'Martha')
[Charles] and his sister [Martha] went to visit their grandmother [Frances] and her husband [James]
[{('James', 'granddaughter', 'Martha'): [('James', 'wife', 'Frances'), ('Frances', 'granddaughter', 'Martha')]}, {('Frances', 'granddaughter', 'Martha'): [('Frances', 'grandson', 'Charles'), ('Charles', 'sister', 'Martha')]}]
['wife', 'grandson', 'sister']