Genesis 35:22-26

While Israel was living in that region, Reuben went in and slept with his father’s concubine Bilhah, and Israel heard of it. Jacob had twelve sons: The sons of Leah: Reuben the firstborn of Jacob, Simeon, Levi, Judah, Issachar and Zebulun. The sons of Rachel: Joseph and Benjamin. The sons of Rachel’s servant Bilhah: Dan and Naphtali. The sons of Leah’s servant Zilpah: Gad and Asher. These were the sons of Jacob, who were born to him in Paddan Aram.