Mosiah 25

 Mormon tells us - 

"...there were not so many of the children of Nephi, or so many of those who were descendants of Nephi, as there were of the people of Zarahemla, who was a descendant of Mulek, and those who came with him into the wilderness.

3 And there were not so many of the people of Nephi and of the people of Zarahemla as there were of the Lamanites; yea, they were not half so numerous.

4 And now all the people of Nephi were assembled together, and also all the people of Zarahemla, and they were gathered together in two bodies."  (Mosiah 25:2–4)

If find it interesting that the Lamanites continued to be more numerous.  I also find it interesting that the people of Zarahemla continued to give all leadership to the people of Nephi.  Mormon never mentions a conflict between the two.