As Lehi desires his family to partake of the fruit, he looks, and sees Sariah, Sam, and Nephi. He doesn’t see the men’s wives. He doesn’t see Ishmael. This is a very personal vision, and it is only his immediate family that becomes the subject. In the case of the husbands, it was presumed that the wives would follow.
As he sees Sariah, Sam, and Nephi, he notes that “they knew not whither they should go.” This is a symbolic dream, and so this part of the dream depicts the family as a general humanity that has not yet received the gospel. All Lehi does is catch their attention, and beckon them to come to him. That was the direction they required. Once they knew where they were to go, they could not only begin, but arrive.
Although this is the eternal goal, it wasn’t the point of the dream. This part of the dream functions as the contrast to the experience with Laman and Lemuel. The dream is about them, and by extension, all who have difficulty in hearing, heeding, and persisting in following God’s path.