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.