Leviticus 21:1-4

And Jehovah said unto Moses, Speak unto the priests, the sons of Aaron, and say unto them, There shall none defile himself for the dead among his people; except for his kin, that is near unto him, for his mother, and for his father, and for his son, and for his daughter, and for his brother, and for his sister a virgin, that is near unto him, that hath had no husband; for her may he defile himself. He shall not defile himself, being a chief man among his people, to profane himself.