[Dale]'s sister, [Nancy], bought movie tickets at a discount rate. [Clarence] was happy that his son [Dale] was doing well in college.
('Clarence', 'Nancy')
[Clarence] was happy that his son [Dale] was doing well in college. [Dale]'s sister, [Nancy], bought movie tickets at a discount rate.
[{('Clarence', 'daughter', 'Nancy'): [('Clarence', 'son', 'Dale'), ('Dale', 'sister', 'Nancy')]}]
['son', 'sister']