And Hagar bare Abram a son: and Abram called his son's name, which Hagar bare, Ishmael. (16:15)

For Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him. (21:2)

And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac. (21:3)

Then again Abraham took a wife, and her name was Keturah. (25:1)

And she bare him Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah. (25:2)

And Jokshan begat Sheba, and Dedan. And the sons of Dedan were Asshurim, and Letushim, and Leummim. (25:3)

And the sons of Midian; Ephah, and Epher, and Hanoch, and Abidah, and Eldaah. All these [were] the children of Keturah. (25:4)

--1 Chronicles--

Now the sons of Keturah, Abraham's concubine: she bare Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah. And the sons of Jokshan; Sheba, and Dedan. (1:32)

And the sons of Midian; Ephah, and Epher, and Henoch, and Abida, and Eldaah. All these [are] the sons of Keturah. (1:33)

And Abraham begat Isaac. The sons of Isaac; Esau and Israel. (1:34)