Genesis 35:22-26

While Israel was living in that land, Reuben went and slept with Bilhah, his father’s concubine, and Israel found out. Jacob had twelve sons. Leah’s sons were Reuben (Jacob’s firstborn), Simeon, Levi, Judah, Issachar, and Zebulun. Rachel’s sons were Joseph and Benjamin. The sons of Rachel’s maidservant Bilhah were Dan and Naphtali. The sons of Leah’s maidservant Zilpah were Gad and Asher. These were the sons of Jacob born to him in Paddan-Aram.