Leviticus 19:3

19:3 Each of you must respect his mother and his father, and you must keep my Sabbaths. I am the Lord your God.

Leviticus 21:2

21:2 except for his close relative who is near to him: his mother, his father, his son, his daughter, his brother,

Leviticus 21:11

21:11 He must not go where there is any dead person; he must not defile himself even for his father and his mother.