Thematic Bible: Specially required to avoid

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, except for his direct relative closest to him: his mother and his father, and his son and his daughter, and his brother, and for his sister, a virgin, [who is] closest to him, {who has not had a husband}--for her he may defile himself. read more.
He must not make himself unclean [as] {a kinsman by marriage}, defiling himself. " 'And they shall not shave bald patches on their head, and they shall not shave off the corner of their beard, and they shall not make a cut in their body. They shall be holy to their God, and they shall not profane the name of their God, because they are bringing near the offerings made by fire to Yahweh--their God's food--and they shall be holy.

And he shall not go near any dead person, nor shall he make himself unclean for his father or for his mother. And he shall not go out from the sanctuary, and he shall not profane his God's sanctuary, because the dedication of his God's oil of anointment [is] on him; I [am] Yahweh.