Kamsa

The reborn demon Kalanemi. Son of Ugrasena, the rulter of Mathura, and his wife Padmavati. Married with Asti und Prapti, daughters of Jarasandha.

Ugrasena’s brother was Devaka, his daughter was Devaki. She married Vasudeva. Devaki and Vasudeva were the parents of Krishna.

Kamsa heard a voice telling him that the eighth child of the couple would kill him. He did not trust and demanded that all of their children be killed.

Vasudeva killed the first six of his children. They were the Sadagarbha, cursed to be killed by their father. They went directly to Vishnu’s abode.

Devaki was the reborn Aditi, cursed by Ditit to lose seven of her childen. The seventh she lost, but it was not killed.

See also Kashyapa

The story is included in the one of the appearance of Krishna
http://hindumythologyforgennext.blogspot.com/2014/04/krishna-dark-lord-of-dwaraka-prelude.html
http://hindumythologyforgennext.blogspot.com/2017/07/little-krishna-part-1.html