20 The descendants of Judah by their clans were: through Shelah, the Shelanite clan; through Perez, the Perezite clan; through Zerah, the Zerahite clan.

Read Numbers 26:20 Using Other Translations

And the sons of Judah after their families were; of Shelah, the family of the Shelanites: of Pharez, the family of the Pharzites: of Zerah, the family of the Zarhites.
And the sons of Judah according to their clans were: of Shelah, the clan of the Shelanites; of Perez, the clan of the Perezites; of Zerah, the clan of the Zerahites.
These were the clans descended from Judah’s surviving sons: The Shelanite clan, named after their ancestor Shelah. The Perezite clan, named after their ancestor Perez. The Zerahite clan, named after their ancestor Zerah.