[Roy] is taking his son [Herman] out for coffee. [Herman] often goes out for lunch with his sister, [Martha].
('Roy', 'Martha')
[Roy] is taking his son [Herman] out for coffee. [Herman] often goes out for lunch with his sister, [Martha].
[{('Roy', 'daughter', 'Martha'): [('Roy', 'son', 'Herman'), ('Herman', 'sister', 'Martha')]}]