Bhishma, a key character in the Mahabharata, is known for the supreme sacrifice of his sex life for the sake of his father.
But this selfless act of his changed the patriarchal nature of the Kuru clan forever.
After Bhishma, we find succession in the Kuru throne becomes matrilineal, with the Kuru throne being handed down through the mother’s bloodline.

For more on the Bhishma story, check this video!