What does 1 Chronicles 23:11 mean?

Shimei also had four other sons: Jahath, Zina, Jeush, and Beriah. Jahath was the oldest, Zizah was the second, but Jeush and Beriah didn’t have many descendants, so they were counted as one family group. 1 Chronicles 23:11 - Modern Text Bible

(Some of Shimei’s sons had smaller families, so they were grouped together for organizational purposes.)