[Robert] invited his grandmother, [Ashley], and his brother, [Jeff], to a live concert at the fairgrounds.
('Jeff', 'Ashley')
[Robert] invited his grandmother, [Ashley], and his brother, [Jeff], to a live concert at the fairgrounds.
[{('Jeff', 'grandmother', 'Ashley'): [('Jeff', 'brother', 'Robert'), ('Robert', 'grandmother', 'Ashley')]}]
['brother', 'grandmother']