Genesis 30:3-9

3And she said, Behold, there is my maid, Bilhah: go in to her, in order that she may bear on my knees, and I may also be built up by her.

4And she gave him Bilhah her maidservant as wife, and Jacob went in to her.

5And Bilhah conceived, and bore Jacob a son.

6And Rachel said, 1God has done me justice, and has also heard my voice, and given me a son; therefore she called his name Dan.

7And Bilhah Rachel's maidservant again conceived, and bore Jacob a second son.

8And Rachel said, Wrestlings of 2God have I wrestled with my sister, and have prevailed; and she called his name Naphtali.

9And when Leah saw that she had ceased to bear, she took Zilpah her maidservant and gave her to Jacob as wife.