Three verses in a row begin with “and it came to pass.” Nephi is moving his story along quickly. The first verse indicates that the ship is built. The second records the command to enter the ship, and the third recounts provisioning the ship for the journey.
What is interesting is the next verse (verse 7). Nephi mentions that he has two brothers born in the wilderness. It is possible that these two were twins, as the first was named Jacob and the younger Joseph. Since Lehi was of Joseph’s lineage, had he had the two sons at different times, we might have suspected that he used that name first. The fact that he didn’t, but went in order of the genealogy, with Jacob first and then Joseph, suggests that both sons were born at the same time so that the naming would make more sense.
Apart from the naming, however, the very presence of this verse is unusual as it is out of time sequence. The sons were born in the wilderness, but not mentioned until now. It appears that when Nephi concluded the previous sentence by mentioning that they all went down into the ship with their wives and children, that he was reminded that he hadn’t noted the birth of the brothers. As Nephi wrote this in the New World and knew that Jacob would be the recipient of this set of plates, he undoubtedly realized that his readers would need to know who he was.
We are seeing Nephi making a last-minute adjustment to his record, triggered by the idea that the whole family, went into the ship—with the specific mention of children being the most likely trigger, as both Jacob and Joseph would have been children at the time.