Genesis 21:10

She said, “Who would have said to Abraham that Sarah would nurse children? For I have borne him a son in his old age.”

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

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

The thing was very grievous in Abraham’s sight on account of his son.

God said to Abraham, “Don’t let it be grievous in your sight because of the boy, and because of your servant. In all that Sarah says to you, listen to her voice. For your offspring will be named through Isaac.

I will also make a nation of the son of the servant, because he is your child.”