Abraham fathered eight sons in total: Ishmael, Isaac and another six to his second wife Keturah, a former concubine.
Isaac had two sons when he was about 60 years old—Esau and Jacob. Jacob (later renamed Israel) had 12 sons who became the fathers of the 12 tribes of Israel.
Ishmael had 12 sons, who lived between Havilah and Shur (east of Egypt in the direction of Asshur). Apparently, they “lived in open hostility toward all their relatives”. This is hardly surprising given the history between Ishmael and his father’s household.
When Abraham died, Isaac and Ishmael set aside their differences and together buried him with his wife, Sarah, at Mamre (near Hebron). Isaac moved south, to live at Beer-la’hai-roi, where decades earlier, God had saved the lives of Hagar and Ishmael.