Genesis 21:11-13

The situation distressed Abraham greatly because of his son [Ishmael]. God said to Abraham, “Do not let it distress you because of Ishmael and your maid; whatever Sarah tells you, listen to her and do what she asks, for your descendants will be named through Isaac. [Rom 9:7] And I will also make a nation of [Ishmael] the son of the maid, because he is your descendant.”