Genesis 21:6-10

And Sarah said, “God has made laughter for me; everyone who hears will laugh over me.” And she said, “Who would have said to Abraham that Sarah would nurse children? Yet I have borne him a son in his old age.” And the child grew and was weaned. And Abraham made a great feast on the day that Isaac was weaned. But Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, laughing. So she said to Abraham, “Cast out this slave woman with her son, for the son of this slave woman shall not be heir with my son Isaac.”