Ezekiel 44:25-27

“A priest must not defile himself by being in the presence of a dead person unless it is his father, mother, child, brother, or unmarried sister. In such cases it is permitted. Even then, he can return to his Temple duties only after being ceremonially cleansed and then waiting for seven days. The first day he returns to work and enters the inner courtyard and the sanctuary, he must offer a sin offering for himself, says the Sovereign LORD.