Genesis 29:31-34

Now the LORD saw that Leah was unloved, and He opened her womb, but Rachel was barren. Leah conceived and bore a son and named him Reuben, for she said, “Because the LORD has seen my affliction; surely now my husband will love me.” Then she conceived again and bore a son and said, “Because the LORD has heard that I am unloved, He has therefore given me this son also.” So she named him Simeon. She conceived again and bore a son and said, “Now this time my husband will become attached to me, because I have borne him three sons.” Therefore he was named Levi.