These are the names of the sons of Aaron: Nadab, the firstborn, and Abihu, Eleazar, and Ithamar.

And to Aaron were born Nadab and Abihu, Eleazar and Ithamar.

This is the service of the families of the Gershonites concerning the tent of meeting. Their responsibilities will be under the authority ¹  of Ithamar son of Aaron the priest. ² 

This is the service of the families of the Merarites, their entire service concerning the tent of meeting, under the authority of Ithamar son of Aaron the priest.”

and he gave four carts and eight oxen to the Merarites, as their service required, under the authority ¹  of Ithamar son of Aaron the priest.

Nadab and Abihu died ¹  before the Lord ²  when they offered ³  strange ⁴  fire ⁵  before the Lord in the wilderness of Sinai, and they had no children. ⁶  So Eleazar and Ithamar ministered as priests ⁷  in the presence of ⁸  Aaron their father.