Numbers 6:7

7 Even if their own father or mother or brother or sister dies, they must not make themselves ceremonially unclean on account of them, because the symbol of their dedication to God is on their head.

Read Numbers 6:7 Using Other Translations

He shall not make himself unclean for his father, or for his mother, for his brother, or for his sister, when they die: because the consecration of his God is upon his head.
Not even for his father or for his mother, for brother or sister, if they die, shall he make himself unclean, because his separation to God is on his head.
Even if the dead person is their own father, mother, brother, or sister, they must not defile themselves, for the hair on their head is the symbol of their separation to God.