Leviticus 21:3

New American Bible - revised edition

or his unmarried sister, who is of his own family while she remains single; for these he may make himself unclean.

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except for his nearest relatives, his mother or father, his son or daughter, his brother

But as a husband among his kindred he shall not make himself unclean and thus profane himself.

A priest’s daughter who is married to an unauthorized person may not eat of the sacred contributions.