Legal Definitions - sister-in-law

A sister-in-law is a family member by marriage, not by blood. The term typically refers to:

• The sister of one's spouse.
• The wife of one's brother.
• It can also commonly refer to the wife of one's spouse's brother.

Here are some examples illustrating this relationship:

• Imagine Sarah is married to Tom. Tom has a sister named Emily. In this scenario, Emily is Sarah'ssister-in-law because she is the sister of Sarah's spouse.

• Consider David, whose brother, Michael, recently married Lisa. For David, Lisa is his sister-in-law because she is the wife of his brother.

• Let's say Maria is married to Alex. Alex has a brother named Ben, and Ben is married to Chloe. In this extended family connection, Chloe is considered Maria'ssister-in-law because she is the wife of Maria's spouse's brother.