Genesis 21:6-10

And Sarah declared, “God has brought me laughter. All who hear about this will laugh with me. Who would have said to Abraham that Sarah would nurse a baby? Yet I have given Abraham a son in his old age!” When Isaac grew up and was about to be weaned, Abraham prepared a huge feast to celebrate the occasion. But Sarah saw Ishmael—the son of Abraham and her Egyptian servant Hagar—making fun of her son, Isaac. So she turned to Abraham and demanded, “Get rid of that slave woman and her son. He is not going to share the inheritance with my son, Isaac. I won’t have it!”