The following is from family search:

Wm Y Mooty
United States, Applications for Headstones for Military Veterans, 1925-1941

other

27 Aug 1911

LaGrange, Georgia

death

27 Aug 1911

Because of the iron cross inscribed on the Confederate headstone we now know according to the regulations it must have been 1930 or after which would dovetail with the above application.

Because of the difference in dimensions with Mary's tombstone as her's is 12' 11/16" wide this does not conform with government regulations as and such I believe her tombstone was privately made probably not long after William Young (Billie) Mooty had his placed at the Mooty Cemetery.