[Clarence]'s daughter, [Nancy], was busy caring for her son, [Jeff], and could n't take his call.
('Clarence', 'Jeff')
[Clarence]'s daughter, [Nancy], was busy caring for her son, [Jeff], and could n't take his call.
[{('Clarence', 'grandson', 'Jeff'): [('Clarence', 'daughter', 'Nancy'), ('Nancy', 'son', 'Jeff')]}]
['daughter', 'son']