Genesis 25:1-18 -- Abraham's other children

Genesis 25:1 Now Abraham had taken another wife, whose name was Keturah, 2 and she bore him Zimran, Jokshan, Medan, Midian, Ishbak, and Shuah. 3 Jokshan fathered Sheba and Dedan. Dedan’s sons were the Asshurim, Letushim, and Leummim. 4 And Midian’s sons were Ephah, Epher, Hanoch, Abida, and Eldaah. All these were sons of Keturah. 5 Abraham gave everything he owned to Isaac. 6 And Abraham gave gifts to the sons of his concubines, but while he was still alive he sent them eastward, away from his son Isaac, to the land of the East.

Now Abraham took another wife and was blesses with many more sons, but Isaac received everything.  Isaac was the chosen one.  He was the one the promise was to be fulfilled through.  I am sure the other sons were well cared and the gifts that Abraham gave them were substantial.

Genesis 25:7 This is the length of Abraham’s life: 175 years. 8 He took his last breath and died at a ripe old age, old and contented, and he was gathered to his people. 9 His sons Isaac and Ishmael buried him in the cave of Machpelah near Mamre, in the field of Ephron son of Zohar the Hittite. 10 This was the field that Abraham bought from the Hittites. Abraham was buried there with his wife Sarah. 11 After Abraham’s death, God blessed his son Isaac, who lived near Beer-lahai-roi.

Abraham was laid to rest next to Sarah, in the land he brought as a burial place from a Hittite man.  It notes that Isaac and Ishmael buried him, so we see the there was still communication between the two brothers, even though Ishmael was sent away when Isaac was very young.

Genesis 25:12 These are the family records of Abraham’s son Ishmael, whom Hagar the Egyptian, Sarah’s slave, bore to Abraham. 13 These are the names of Ishmael’s sons; their names according to the family records are: Nebaioth, Ishmael’s firstborn, then Kedar, Adbeel, Mibsam, 14 Mishma, Dumah, Massa, 15 Hadad, Tema, Jetur, Naphish, and Kedemah. 16 These are Ishmael’s sons, and these are their names by their villages and encampments: 12 leaders of their clans. 17 This is the length of Ishmael’s life: 137 years. He took his last breath and died, and was gathered to his people. 18 And they settled from Havilah to Shur, which is opposite Egypt as you go toward Asshur. He lived in opposition to all his brothers.

Ishmael lived in opposition to all his brothers, as was promised by God.  Here we see that Ishmael had 12 sons, each of whom became their own tribe, just like Jacob (Isaac's son) had 12 sons.