The Bhishma in ''The Mahabharata'

I just read through 'The Mahabharata' and i found the similarities between Bhishma and the maiden in 'The Son of The Turtle-Spirit'. They both are witty enough to help their beloved ones to achieve their dreams. Instead, Bhishma is a noble person that he is willing to give up the throne for his father's happiness. Besides, he even swears to have no sons just to help his father to marry another girl. Nevertheless, the story I read is just a part of the whole complete story of ''The Mahabhrata'. So, I believe that the story will not end in this simple way. There will sure be some conflicts happen in the later parts of the story. This story is indeed inspiring and exciting. I'm looking forward to the class when our lecturer, Dr. Edwin, discusses about it.

' The Son of the Turtle-Spirit'

This is the first piece of literature we are required to read by our lecturer. After reading it, I am attracted by the maiden's character. She is a clever mother who is able to help her son to succeed. Also, she shows gratitude to the man she loves. Despite knowing the real identity of her 'husband', she still keeps his bones with her and does not throw it away. It is an interesting story based on Chinese culture, yet there's something that I'm not clear with: Since the turtle can change his form into a man, why is that he doesn't help himself to escape from being killed by the maiden's father??