There is no indicated kinship connection between Mormon and Ammaron. Certainly Ammaron knew Mormon’s family, or else he would hardly have noticed a ten year old child enough to proclaim him “a sober child, and … quick to observe.” The Lord certainly had a hand in the selection of Mormon, but it is equally as certain that the Lord made certain that Mormon was in a sphere of acquaintance where Ammaron would understand to whom the promptings of the Spirit would refer. It would not be unusual for there to be a kinship connection that explains the reason that Ammaron would have known of Mormon.
If there was a kinship connection, it was not a direct one that invoked the lineal lines of transmission. When Amos the father of Amos gives the plates to another, it is to his son. When Amos the Younger gives the plates, it is to his brother. This sibling transmission is one that we have seen before (Nephi to Jacob and Amaron to Chemish: Omni 1:4-8;) It is also a known facet of later Aztec royal inheritance, where the brother might inherit prior to the sons in certain instances. Had Mormon been a son or brother, we would expect that the normal transmission would have been followed.
We do not have any information on the circumstances that caused Ammaron to bury the plates, but we have speculated that it was the result of a coup that ousted his family from rule. If this is correct, then we would not expect Mromon to be a close kin, or else he would have been too closely watched as a potential claimant to the throne. Whatever danger Ammaron saw in keeping the plates himself would then have pointed directly at Mormon.
Although it is pure speculation, the best explanation for passing the plates to Mormon in this fashion was that Ammaron was ousted from political favor, and that he went to someone that was known to him, but distant. If there was a kin relationship, it would be one explanation for a way that Ammaron would know Mormon’s father, and therefore have a means of knowing Mormon. If there were a kinship connection, however, it would have to have been distant or else Mormon would have been under the same danger that caused Ammaron to bury the plates in the first place.
A second possible way in which Ammaron would have had a connection to Mormon would have been that Mormon’s father could have been a court retainer for Ammaron as ruler. This might allow Mormon’s father to be an acquaintance, but not kin. The advantage of this proposal is that it makes it even more likely that there was enough social distance between Ammaron and Mormon that whatever dangers Ammaron perceived could be deflected from Mormon.
[art quick to observe]: There are two ways of reading this phrase. Mormon would be “quick to observe” might mean that he learned quickly. The “observation” would then be related to his intelligence and learning. In this connection we might suppose that Ammoron was in a position to note Mormon as a student. Ammaron would be particularly interested in Mormon’s ability to learn to read and write, traits that would be required for Mormon to complete the task that Ammaron was to request of him. This suggests that Mormon would have been in the court of Ammaron learning this skill. Mesoamerican practice suggests that those who learned to read and write were those who were peripheral nobles outside of the inheritance lines. This is, of course, exactly where our speculation places Mormon.
A second reading of “observe” would be that Mormon was quick to observe the laws of the gospel. In this reading the emphasis would be on Mormon’s religious devotion. While this is possible, given the nature of Ammaron’s request, it would seem more likely that Ammaron’s interest in a ten year old boy would have more to do with his ability to read and write that his piety. That would have been important, but it might also have been assumed based upon knowledge of the family and the heritage. The ability to read and write would be paramount, and not necessarily typical of a ten year old.