Book of Mormon: Ammon or Aaron–Who Was Older?

Book of Mormon: Ammon or Aaron–Who Was Older?

In Mosiah 27:34, we learn that king Mosiah has four sons, and it names Ammon first, then Aaron. So, it seems that Ammon is the firstborn, and Aaron is the second. This way of giving birth order happens at other times: with Lehi’s sons, with Alma the Younger’s sons, and with Helaman’s sons, for example. However, there are a few things that make me wonder if Ammon really was the firstborn, or at least conclude that there’s more to the story than what is written.

Many people point to Ammon’s being the leader of the missionary group (Alma 17:18 ) as extra evidence of his being the firstborn; but this is a church calling, not something that has to do with age or birth order. In addition, being called the people of Ammon has to do with religious things, too, as does being high priest over them (Alma 30:20).

I see three hints that Aaron might be older:
1. while Ammon preaches to the lesser king/ prince Lamoni, it is left to Aaron to preach to the king of all the Lamanites; is that the Nephite prince teaches the Lamanite prince, and the rightful Nephite king teaches the king?
2. when the Lamanite king wants a new name for his converted people, he consults chiefly with Aaron (Alma 23:16; 17-18). Perhaps choosing a new name is more of a political decision than a religious one; consulting with the heir king and getting his approval is more appropriate. Also, the two verses afterwards, are political matters.
3. the people ask that Aaron be king, and king Mosiah says it’s Aaron’s right to be king (Mosiah 29:1-3, 6). When king Mosiah speaks about potential future problems with the right to rule the kingdom, including the possible return and oath dismissal by those who had a past right to rule as king, he speaks about Aaron–never Ammon.

So, why would Aaron have the right to rule if Ammon were the firstborn?

Was Aaron really older than Ammon, but played a less prominent role in the spiritual aspect in the Book of Mormon? Or maybe Ammon swore he would never be king. (But if that had been the case, wouldn’t king Mosiah also have spoken about that in Mosiah 29?) Could Ammon have done something much earlier to lose his right to rule, to lose his right of the firstborn–something that Aaron hadn’t done? (But weren’t they all in it together?) Was a mistake made in the writing? Was the name placing in Mosiah 27:34 done for some other reason? I don’t know.

At least, I think it would be much better to say they are brothers, than to say that Ammon is definitely older than Aaron.

Any other insights, scriptures?

[EDIT, July 7, 2017:  This topic came to my thoughts much more because of the Chinese translations of the Book of Mormon, where “older brother” is used for Ammon, and “younger brother” is used for Aaron.]