Genesis 35:22-26

22While Israel was living in that land, Reuben [his eldest son] went and lay with Bilhah his father’s concubine, and Israel heard about it. Now Jacob had twelve sons—

23The sons of Leah: Reuben, Jacob’s firstborn, then Simeon, Levi, Judah, Issachar, and Zebulun;

24and the sons of Rachel: Joseph and Benjamin;

25and the sons of Bilhah, Rachel’s maid: Dan and Naphtali;

26and the sons of Zilpah, Leah’s maid: Gad and Asher. These are the sons of Jacob born to him in Paddan-aram.