Numbers 4:22 in the King James Version
Take also the sum of the sons of Gershon, throughout the houses of their fathers, by their families;
Context
21 The LORD spoke to Moses, saying,
22 “Take a census of the sons of Gershon also, by their fathers’ houses, by their families;
23 you shall count them from thirty years old and upward until fifty years old: all who enter in to wait on the service, to do the work in the Tent of Meeting.