Genesis 29:30-34

30Jacob slept with Rachel also, and indeed, he loved Rachel more than Leah. And he worked for Laban another seven years.

31When the Lord saw that Leah was neglected, he opened her womb; but Rachel was unable to conceive.

32Leah conceived, gave birth to a son, and named him Reuben, for she said, “The Lord has seen my affliction; surely my husband will love me now.”

33She conceived again, gave birth to a son, and said, “The Lord heard that I am neglected and has given me this son also.” So she named him Simeon.

34She conceived again, gave birth to a son, and said, “At last, my husband will become attached to me because I have borne three sons for him.” Therefore he was named Levi.