Genesis 48:17-20

When Joseph saw that his father laid his right hand on Ephraim’s head, it displeased him [because he was not the firstborn]; and he grasped his father’s hand to move it from Ephraim’s head to Manasseh’s head. Joseph said to his father, “Not so, my father, for this is the firstborn; place your right hand on Manasseh’s head.” But his father refused and said, “I know, my son, I know; Manasseh also will become a people and he will be great; but his younger brother shall be greater than he, and his descendants shall become a multitude of nations.” Then Jacob blessed them that day, saying, “By you Israel will pronounce a blessing, saying, ‘May God make you like Ephraim and Manasseh.’ ” And he put Ephraim before Manasseh.