Double grave site?

As you all know, I am heavily into Genealogy.  There is a cemetery down the line that my Great Grandparents are buried in.  I've been there once, found the only family stone, took pictures and came home very happy.  Yes, I found the site and the open land where everyone was buried.  The person who has volunteered to bring this cemetery back to health has contacted me about the gravesite of an Uncle.  He was going to take pictures of the stone for me.  It is nice to have someone else's perspective on this.  So the pictures show up and they are not the same stone that I have!  The birth date is wrong but the death date is the right one.  It also states he was in the War and has a military flag on it.  So, who has the right stone?  Did John have 2 stones?  If so, why?  Stay tuned.  Another puzzle to solve......