Jether

“Moreover you know also what Joab the son of Zeruiah did to me, even what he did to the two captains of the armies of Israel, to Abner the son of Ner, and to Amasa the son of Jether, whom he killed, and shed the blood of war in peace, and put the blood of war on his sash that was around his waist, and in his shoes that were on his feet.

Yahweh will return his blood on his own head, because he fell on two men more righteous and better than he, and killed them with the sword, and my father David didn’t know it: Abner the son of Ner, captain of the army of Israel, and Amasa the son of Jether, captain of the army of Judah.

Abigail bore Amasa; and the father of Amasa was Jether the Ishmaelite.