I heard that while KamsaKamsa was dying, he cursed Shri Krishna that he (Shri KrishnaShri Krishna) will also die in the hands of his nephew.
Shri Krishna had only one sister i.e SubhadraSubhadra. So, while she was pregnant, Shri Krishna was telling her the secret of ChakravyuhaChakravyuha, as it was a boring topic for her, she slept soon but the child inside her womb was listening to Shri Krishna's explanation.
The child was acknowledging that he is listening to the explanation by doing hmm sound frequently.
I heard that:
Shri Krishna told the child about how to enter the ChakravyuhaChakravyuha but not thehow to exit one.it so that the child will die in ChakravyuhaChakravyuha and Shri Krishna can get rid of the curse. (Some other sources says that Arjuna was explaining the chakravyuha to Subhadra, when he explained the entering of chakravyuha, Shri Krishna interrupted him and took him away)But some other sources say that Arjuna was explaining the Chakravyuha to Subhadra, when he explained the entering of Chakravyuha, Shri Krishna interrupted him and took him away.
And also during the battle (MahbharataMahabharata), Shri Krishna as a charioteer diverted Arjuna's (who is aware of Chakravyuhawho is aware of Chakravyuha) Chariot far from the ChakravyuhaChakravyuha when Abhimanyu was entering in to it.
Is this true?
PS: There were other nephews of Shri Krishna known as upapandavasupa-pandavas. Though they weren't in direct relation with shriShri Krishna, they died on the night of the end of mahabharataMahabharata war.