I think they should have gotten married in Mississippi but it was during the Civil War so records are scarce or mostly non-excise. I don't have anything but the fact they had a child in 1865 but by then the dad was out of the picture and mom was remarried by the 1870 census.
All I have is a map of the counties around
From there I just need to keep looking for any sign of him in earlier census records.
I have found out that Mary Lue moved after her birth to Lafayette, Mississippi so that is another lead but it does not do much, just leads in in another direction. Still I am no closer to Robert than I was.
After days on end of searching I began to drift over to my other love, my TPT site and I worked on a couple of new products for sale. But all the while I was still thinking of my past grandfather. Think of things that might have happened to him. Things like I know he was not killed during the Civil War due to the fact that his son was born that final year of the war. But something happen to him due to the fact that my past grandmother remarried short after in 1668 from the stories I have read.
Odds are he died in Texas on or near the birth of his child but I can't find any records. So that leaves me just looking, reading, searching, and digging. what was going on in north Texas during that time? I don't know but I'm still looking while I'm working on other things - when something news hits me.