GRAVES, John M. (Mimms)., 13 Jan 1812 - 29 Apr 1879. "Father" & Rosa 
A. (Rosa Ann Collier)., 12 Mar 1817- 29 Jul 1907. "Mother". 
The stone back to your left with the pointed top is also a John M Graves inscribed as: John M. Graves Born 1812, 
Died May 1, 1879, Aged 67. This was probably an earlier stone installed without his spouse.