One set of possible parents for Charles Bastian is Heinrich (Henry) and Natalie Hartenstein Bastian. I found this one first linked to someone's tree for a person that I know is related to my great-grandfather, so I followed the lead for awhile. Although it is always possible that I will be wrong, I do not believe this is the correct set of parents for my great-grandfather.
There are two prime reasons that I have this belief. First, the Heinrich and Natalie Hartenstein Bastian family centered in Austin, Texas, not Austin County, Texas. Although not terribly far apart, these are not the same place. Second, Heinrich and Natalie Hartenstein Bastian have a son born about the same time, but all records I have found so far show his name as Carl, not Charles. Carl Bastian from this family also died as a child. I believe that those using this connection have decided that Charles and Carl are the same person, and do not know that Austin and Austin County are two different places. In fact, one tree I found even showed the name to be Charles Carl, officially linking the two names.
The sad part is that this Bastian family has a bit of information available in research terms, and the story is interesting. I have not discarded the research I found; just removed it from my tree once I became relatively certain there is not a link there. It may turn out in the future that these are cousins further back. This family came from Germany, which is where I believe my great-grandfather's parents came from (according to census records). There are many names used repeatedly in both families (Otto, Henry, and Charles).
So, the search continues!