“Take a census of the sons of Gershon also, by their fathers’ households, by their families;
And these are the names of the sons of Gershon by their families: Libni and Shimei;
Of Gershon was the family of the Libnites and the family of the Shimeites; these were the families of the Gershonites.
and the leader of the fathers’ households of the Gershonites was Eliasaph the son of Lael.
Then Yahweh spoke to Moses, saying,
from thirty years and upward to fifty years old, you shall number them; all who enter to perform the duty of performing the service in the tent of meeting.