Narrative analysis: From the standpoint of creating the tension of the story line, the calling of Sariah, Sam, and Nephi as a set establishes Lehi's family as part of the vision, and clearly establishes the ability of his family to hear Lehi and his words.
Symbolic analysis: When Lehi calls to Sariah, Sam, and Nephi, they hear their father. Even more, they believe what he has told them, and act upon it. This simple act is symbolic of our call to the Savior, and the ability of those who are able to hear and recognize his voice to come unto him. The strength of the vision for our world, however, lies not so much in the simple ability of those who hear to come and partake, but the recognition that the process is not nearly so simple for many in this world. In contrast to those depicted in the rest of the vision, the simple faith of Sariah, Sam, and Nephi is remarkable.