[April] was worried about her graduation party. Her mother [Lillian] had turned up earlier that day, but her brother [John] was still missing.
('Lillian', 'John')
[April] was worried about her graduation party. Her mother [Lillian] had turned up earlier that day, but her brother [John] was still missing.
[{('Lillian', 'son', 'John'): [('Lillian', 'daughter', 'April'), ('April', 'brother', 'John')]}]
['daughter', 'brother']