Genesis 46:12
And the sons of Judah; Er, and Onan, and Shelah, and Pharez, and Zerah: but Er and Onan died in the land of Canaan. And the sons of Pharez were Hezron and Hamul. And the sons of Judah; Er, and Onan, and Shelah, and Pharez, and Zerah: but Er and Onan died in the land of Canaan. And the sons of Pharez were Hezron and Hamul.
The listing belongs to the time of famine that reached Canaan where Jacob was dwelling, when word of abundant provision in Egypt sent ten of Jacob's sons on the journey there to buy grain. Benjamin was not among the ten travelers but stayed behind with his father, while Joseph was counted as the one who is not, so that there were twelve brothers in all. On arriving, the ten came before the ruler of Egypt and bowed down with their faces to the earth, not knowing who he was.
Joseph, as prime minister, knew them even though he bore an Egyptian name and his appearance had changed, while they failed to recognize him. The sight of his brothers stooping before him in obeisance brought his former dreams back to his mind.