Genesis 25:1-6

Abraham took another wife, whose name was Keturah. She bore him Zimran, Jokshan, Medan, Midian, Ishbak, and Shuah. Jokshan fathered Sheba and Dedan. The sons of Dedan were Asshurim, Letushim, and Leummim. The sons of Midian were Ephah, Epher, Hanoch, Abida, and Eldaah. All these were the children of Keturah. Abraham gave all he had to Isaac. But to the sons of his concubines Abraham gave gifts, and while he was still living he sent them away from his son Isaac, eastward to the east country.