She also said, “Who would have said to Abraham that Sarah would nurse children? For I have borne him a son in his old age.”
Hagar and Ishmael Depart
So the child grew and was weaned. And Abraham made a great feast on the same day that Isaac was weaned.
Genesis 21:7-8 (NKJV)
Some Bible translation include their own commentary by way of section headings. The NIV and the NKJV both include a “Hagar and Ishmael Sent Away” header, but this shifts the focus and loses the story.
The entire point of this bit is that a very old woman is nursing a child!
Sarah said, “God has made laughter for me; everyone who hears will laugh with me.” And she said, “Who would have said to Abraham that Sarah would nurse children? Yet I have given birth to a son in his old age.”
And the child grew and was weaned, and Abraham held a great feast on the day that Isaac was weaned.
Sarah Turns against Hagar
Now Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, mocking Isaac.
Genesis 21:6-9 (NASB)
The NASB inserts “Sarah Turns against Hagar” after verse 8, keeping the nursing and the weening segments together, but then it breaks up the *laughter* from v6 from the connected laughter in verses 9 and 10.
The story is much clearer without the section headings.