Genesis 21:9 DBY

⁷  And she said, Who would have said to Abraham, Sarah will suckle children? For I have borne [him] a son in his old age.

⁸  And the child grew, and was weaned. And Abraham made a great feast on the day that Isaac was weaned.

⁹  And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, mocking.

¹⁰  And she said to Abraham, Cast out this handmaid and her son; for the son of this handmaid shall not inherit with my son -- with Isaac.

¹¹  And the thing was very grievous in Abraham's sight because of his son.