Numbers 6:7
for even his father, mother, brother, or sister he will not make himself unclean {by their death}, because the separation to his God [is] on his head.
Numbers 9:6
And it happened, men who were unclean {by a dead person} were not able to perform the Passover on that day. And they came {before} Moses and Aaron on that day.
Leviticus 21:1-2
Then Yahweh said to Moses, "Speak to the priests, Aaron's sons, and say to them, 'One must not make himself unclean for a dead person among his [own] people,
Leviticus 21:10-12
" 'As for the priest [who is] higher than his brothers, on whose head the oil of anointment is poured and {he was ordained} to wear the garments, he shall not dishevel his head, and he shall not tear his garments.
Ezekiel 44:25
And {near a dead person} he shall not come to be defiled, {but only} for a father and for a mother and for a son and for a daughter, for a brother and for a sister {who was not married} may they defile themselves.