Daily AncestorSister-in-law
A sister-in-law is the sister of your husband or wife, or the wife of your brother.
Sister-in-law means either your spouse's sister or your brother's wife. A sister-in-law living in a household, common in census records, may be the wife's unmarried sister or a brother's widow.
Her surname is a clue: a spouse's sister usually carries the spouse's maiden surname, while a brother's wife or widow shares the head's surname.
As seen in a recordRelationship column of the 1880 census
Ann Ross, Sister-in-law, S, 32
How to cite this page
Daily Ancestor. "Sister-in-law." Dictionary of Old Record Words. https://dailyancestor.com/dictionary/relationships/sister-in-law. Last checked 2026-10-01.