sons.

Numbers 3:19
The sons of Kohath by their clans were Amram, Izhar, Hebron, and Uzziel.

Numbers 26:57
Now these were the Levites registered by their clans: The Gershonite clan from Gershon, the Kohathite clan from Kohath, and the Merarite clan from Merari.

1 Chronicles 6:2, 18
The sons of Kohath: Amram, Izhar, Hebron, and Uzziel. . . .

and the years

Exodus 6:16
These were the names of the sons of Levi according to their records: Gershon, Kohath, and Merari. Levi lived 137 years.