For 50+ years my grandmother has tended the twins' grave, and there have been many times when Grandpa and I were with her. On more than one occasion, Pa would mention that the twins were buried not long before "they started baby land." He would always point in a general direction, but I never noticed any obvious special section for infants.
On a recent visit to Magnolia Park, I stumbled across this "baby land" section. It is located in the central section behind the oldest graves, which are behind the main sign for the cemetery. All the markers are tiny and flat, and there are quite a few. If you are not careful, you will be stepping on one before you know it. I'm sure there are even rows, but I believe some of the markers may already be lost for whatever reason (maybe some graves never had them). This is a very well maintained cemetery, but the markers I saw are in too much of a scattered pattern for me to think what we see today is all there ever were.
Here are a couple of photos of the types of markers found in "baby land."
I Pray The Lord My Soul to Keep
Nov 1, 1962 - Nov 2, 1962