TSK · Genesis 16:2

The man said,“The woman whom you gave me, she gave me some fruit from the tree and I ate it.”

But Sarai was barren; she had no children.

One of them said,“I will surely return to you when the season comes round again, and your wife Sarah will have a son!”(Now Sarah was listening at the entrance to the tent, not far behind him.

Isaac prayed to the LORD on behalf of his wife because she was childless. The LORD answered his prayer, and his wife Rebekah became pregnant.

She replied,“Here is my servant Bilhah! Sleep with her so that she can bear children for me and I can have a family through her.”

When Leah saw that she had stopped having children, she gave her servant Zilpah to Jacob as a wife.

If his master gave him a wife, and she bore sons or daughters, the wife and the children will belong to her master, and he will go out by himself.

Yes, sons are a gift from the LORD, the fruit of the womb is a reward.