Jether

Now Absalom appointed Amasa in Joab's stead over the army: and Amasa was the son of a man who was called Jethra, of Jezrael, who went in to Abigail the daughter of Naas, the sister of Sarvia who was the mother of Joab.

Thou knowest also what Joab, the son of Sarvia, hath done to me, what he did to the two captains of the army of Israel, to Abner, the son of Ner, and to Amasa, the son of Jether: whom he slew, and shed the blood of war in peace, and put the blood of war on his girdle that was about his loins, and in his shoes that were on his feet.

And the Lord shall return his blood upon his own head; because he murdered two men, just and better than himself: and slew them with the sword, my father, David, not knowing it; Abner, the son of Ner, general of the army of Israel, and Amasa, the son of Jether general of the army of Juda;

And Abigail bore Amasa, whose father was Jether the Ismahelite.