Leviticus 10:4

And Moses called Mishael and Elzaphan, the sons of Uzziel, the uncle of Aaron, Exodus 6:18, and his own cousins, and said unto them, Come near, carry your brethren from before the Sanctuary out of the camp. The two dead men were the brethren, the relatives, of the men who were to perform the last rites over them: and they were buried in their linen coats, for these priestly garments had been defiled with the dead bodies.