I found the grave of Joseph Llewellyn by surfing on the Internet. He died at 5 years old on May 9, 1875. Local Historian Wilma Caddel gave me exact directions to the grave. I had actually passed this spot the week before going off an Internet direction. If you come off Buena Vista(1446) from Waxahachie you take a left on Hoyt. It has a sign at Hoyt and 1446 that points to the Fri-Tex Dairy Farm and Hoyt runs beside the abandoned SSC buildings. The road goes straight to the entry to the Dairy Farm but you take the curve to the left and travel about a half mile. Inside a barbed wire fence on the left not to far from the road is the grave with an iron fence around it and a tree next to it. It is on private property and it looks like they keep it up. It appeared nobody was there so I didn't bother to ask to get inside fence. The location is approximately here.
The story on the internet goes as follows.
Located 6 miles West of I35 on Buena Vista Rd., Right at SSC Lab to Fri-TEX Dairy; .5 miles West of Dairy. Grave is on the left. (There is a story that this grave is that of a child who was riding with his family on a wagon train, and was killed by Indians. The grave is that of Joseph Llewellyn who died May 9, 1875; he was age 5 years 5 months.)
(ECGS Volume 11)
Now, I'm thinking the Joseph's body was carried to this spot maybe at the end of their journey. There were not many skirmishes with Indians in Ellis County, especially by 1875. This fact makes me think the skirmish happened somewhere else on their journey.
Another link is here