[Robert] and his son [Wayne] are going to eat lunch with [Ashley], [Robert]'s grandmother.
('Wayne', 'Ashley')
[Robert] and his son [Wayne] are going to eat lunch with [Ashley], [Robert]'s grandmother.
[{('Wayne', 'mother', 'Ashley'): [('Wayne', 'son', 'Robert'), ('Robert', 'grandmother', 'Ashley')]}]
['son', 'grandmother']