The Grave with Greener Grass (Sly Harrell 'Finder' Series)

A descendant of one of Florida's first families pursues a family ritual with the promise of a treasure at its solving. Annually, the senior living female of the heritage line is obligated to stand in front of a gravestone and recite from a letter passed from mother to daughter. The major clue: the grass covering the grave is always greener than those around it. But why? And after over a hundred years is the clue meaningless?