This is one of those things that makes you go Hmmmmmm... It is possible Richard was married to Narcissus Matilda Merrill in Missouri, that she died in the Dallas area, and Melvina was sent to live with her uncle. It is also possible we have two different Richard Jacob Allens. This ought to keep me busy for a while!
Who were the children of Richard and Mary?
Nothing I have on this family is proven, only what I found in the Historical Society publication of McCullough County, TX. I believe their information was based on word of mouth from the family, and I have no idea where the familie's info came from.
I'll keep working on this and let you know what I find out.