How and why did Ephraim get the birthright? Of the 14 men who were eligible, Ephraim was the youngest.

Reuben should have been the recipient. He lost the birthright because of unworthiness.

Simeon was Jacob's second son, but the birthright doesn't pass according to birth order. The birthright goes to the first son. If the first son loses it, it passes to the first son of the second wife.

Jacob had 10 sons by three wives before Rachel, his second wife, finally had a baby. That baby was son number 11, but was the firstborn of the second wife. That son was Joseph. The birthright became his. That meant that he would inherit double what the other heirs would get, but that he also would become head of the family, and have the responsibility for their care. His care ultimately saved their lives.

Just before Jacob died, he had Joseph bring Joseph's two sons for a patriarchal blessing. He told Joseph that any subsequent children that Joseph would have would be Joseph's, but that Manasseh and Ephraim were now his (Jacob's). He then purposefully gave the birthright to Ephraim. That was how the Lord willed it. By claiming Joseph's two boys, Joseph got a double inheritance, and the birthright passed from Joseph to Ephraim.

We know nothing about Ephraim or about what sort of person he was. Was he a stellar example like his father? We don't know.

For the next 400 years or so, the Israelites in Egypt kept track of which tribe they were descended from. Everyone was able to state their lineage. When they reached Palestine and the tribes were assigned areas for their inheritance, everyone knew where they belonged.

At the death of Solomon, Israel split into two nations. The northern kingdom was made up of 10 tribes, led by the tribe of Ephraim. Consequently the northern kingdom was most often referred to as "Ephraim," and the southern kingdom was called "Judah."

Here in the latter days Ephraim is still the leader. The patriarchal blessings of most Latter-day Saints declare that they are of the tribe of Ephraim. This is the tribe to which all of the other tribes will have to come to receive their blessings. It is Ephraim that is building temples, and it is under the hands of Ephraim that the other tribes will receive their endowments and sealings.

It is by design that these members of the Church came to earth in this lineage. Ephraim has the assignment to lead the way, and to provide blessings to the rest of the family.