[Clarence] sat his grandson [Tony] on his knee and asked him what he wanted to be when he grew up. [Tony] said he wanted to be an astronaut. [Tony] tripped his brother [Travis] in the living room.
('Clarence', 'Travis')
[Clarence] sat his grandson [Tony] on his knee and asked him what he wanted to be when he grew up. [Tony] said he wanted to be an astronaut. [Tony] tripped his brother [Travis] in the living room.
[{('Clarence', 'grandson', 'Travis'): [('Clarence', 'grandson', 'Tony'), ('Tony', 'brother', 'Travis')]}]
['grandson', 'brother']