And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, scoffing.
Genesis 21:9
Surrounding context
21:8 So the child grew and was weaned. And Abraham made a great feast on the same day that Isaac was weaned.
21:9 And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, scoffing.
21:10 Therefore she said to Abraham, "Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, namely with Isaac."