The Stick of Ephraim, according to Ezekiel 37:19 is the Book of Mormon, a nation and people. The Firstborn role of the House of Joseph in the last days, is to ingather his Hebrew family and offer them salvation through the bread of Yeshua.  After Judah is restored to the first principles of the gospel (through Joseph who are the no people of Deut 32:21), the greater things of the Torah of Hashem comes forth form a restored residue of the House of Judah to Joseph and the two houses become one again, as in the days of David.