Which is correct sisters-in-law or sister-in-laws?

Answer 1

Sisters-in-law is the correct plural, referring to two or more women who are each your sister-in-law.

Sister-in-law's is the possessive form, describing a characteristic or object that belongs to one sister-in-law.

Sisters-in-law's is the plural possessive, describing something belonging to both sisters-in-law.

Answer 2

The correct plural of sister-in-law is sisters-in-law, with an s on the end of sister but no s on the end of law.

The same rule applies to brothers-in-law, fathers-in-law, mothers-in-law, etc.

Answer 3

Neither is correct. The correct forms are presented for you in the sentences below:

• "This is my sister-in-law Jane" - when introducing the wife of your brother John

or

• "These are my sisters-in-law Jane and Anne" - when introducing the wives of your brothers John and Peter.

The "law" (i.e., marriage) pertaining to the sisters is singular and constant in both cases, it is the plurality of the sisters that changes.

Answer 4

Your sister would share common parents with you. Your sister-in-law is either married to your brother, or is the sister of you spouse.

Answer 5

sisters-in-law