The issue is consistency in indexing all of the records on FamilySearch.org not necessarily the grammatically correct way to express the term mother in law. From: "Jim Tarbet" >I have been indexing the 1940 census for the last month or so, and have > constantly had one phrase marked as incorrect that I don't believe > should be, nor is incorrect. Perhaps someone on this list can confirm > the correct way to write the term "Son in Law", or "Mother in Law" . > Those who review my indexing entries insist the these phrases should be > entered as "Son-In-Law" or "Mother-in-Law", always using the hyphens. > I don't believe the hyphens are required grammatically.