Genesis 21:9 in the World English Bible
Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, mocking.
Context
8 And the child grew, and was weaned: and Abraham made a great feast the same day that Isaac was weaned.
9 And Sarah saw the son of Hagar the Egyptian, which she had born unto Abraham, mocking.
10 Wherefore she said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.