On my grandparents' living room wall are portraits of three prophets: Thomas S. Monson, Joseph Smith, and David O. McKay. The first two are probably on many Mormon walls all across the world: it makes a certain amount of sense to give special attention to the current prophet and the first prophet of the Restoration. It also makes a certain amount of sense not to include all the latter-day prophets in one's living room--16 portraits might be a bit overwhelming to visitors. Three is a much more reasonable number of prophets to display to guests, but why choose David O. McKay over, say Lorenzo Snow or Spencer W. Kimball?
The answer in our case is very simple: David O. McKay was the prophet when my grandfather immigrated from Punjab to the United States and joined the LDS church. Joseph Smith may have been the church's first prophet, but David O. McKay was my grandfather's first living prophet, and as such will always carry a special place in his heart, and probably in our family's hearts for generations. My family history and spiritual history are intertwined: my sense of what is spiritually significant may always be colored by my grandparents' experience as well as my own.
While we know that Nephi's family history was important to him, it's hard to be specific about the details, since we don't have them written down. In the books of Nephi, we learn about Nephi's parents and religious identity and get scattered references to Joseph as an ancestor, but that's it. Not until Alma 10: 2 do we learn that Lehi was from the tribe of Manasseh. The Book of Mormon gives us no clues as to what a community of Manasseh's descendants, heirs to the northwest, might have been doing in Jerusalem, a city so associated with the tribes of the south.
For that, you'll have to look in the Bible.
Latter-day Saints don't tend to spend a lot of time in the book of 2 Chronicles: two weeks every four years if you're sticking to the gospel doctrine class member guides, which is a lot better than most of us do. Which is why you're probably not casually acquainted with the story of Hezekiah's Passover in 2 Chr. 30. By the time of this story, the northern kingdom of Israel had long since fallen into apostasy and idolatry, and the southern kingdom of Judah had been just as bad more often than not. Hezekiah, though, was righteous, and had even selected a prophet named Isaiah as his most trusted advisor. After cleaning up his own kingdom, Hezekiah sent messengers to the northern tribes inviting them to come and celebrate the Passover in Jerusalem according to the law, joining in the revival. Many "laughed them to scorn" but "divers of Asher and Manasseh and of Zebulun humbled themselves, and came to Jerusalem."
Could it be that Lehi's own grandfather was among that group? Did Isaiah mean to him and his sons what David O. McKay meant to my grandfather, and through him, to me?