[Ernest] has a brother who is younger than him. The brother has a sister whose name is [Martha]. [Ernest] was so excited to introduce his new girlfriend to his mother, [Mary].
('Mary', 'Martha')
[Ernest] was so excited to introduce his new girlfriend to his mother, [Mary]. [Ernest] has a brother who is younger than him. The brother has a sister whose name is [Martha].
[{('Mary', 'daughter', 'Martha'): [('Mary', 'son', 'Ernest'), ('Ernest', 'sister', 'Martha')]}]