I don't think that Violetta is buried in the Center or Campground area. I do know that Mary Ann first appeared over there when she first came to Arkansas. She has a second set of twins and one of them died (Lynn) and was buried I think in the Campground cemetery.
I agree that she probably doesn't have a tombstone. I believe she may be buried in a cemetery (don't know the name of it) between Horseshoe Bend and Myron. There are several Gilbreaths buried there, some are her children.
My late husband was a grand-nephew of hers. His grandfather was Charles, a brother of Violetta.
Rose Mary Lankford