According to the author of Chronicles, Shimei had many sons and daughters, but his brothers did not have as many children, so their family did not grow as much as the people from Judah. This story shows that some families grew larger than others during that time.
1 Chronicles 4:27: And Shimei had sixteen sons and six daughters; but his brethren had not many children, neither did all their family multiply, like to the children of Judah. [like...: Heb. unto]
It states that the sons of Simeon were numerous, contradicting 1 Chronicles 4:27 which mentions that the sons of Simeon did not multiply.
1 Chronicles 4:38: These mentioned by [their] names [were] princes in their families: and the house of their fathers increased greatly. [mentioned: Heb. coming]