Leviticus 18:10

18:10 You must not expose the nakedness of your son’s daughter or your daughter’s daughter by having sexual intercourse with them, because they are your own nakedness.

Leviticus 20:19

20:19 You must not expose the nakedness of your mother’s sister and your father’s sister, for such a person has laid bare his own close relative. They must bear their punishment for iniquity.