Hania, thank you for this suggestion. Yes, there could very well be a good chance that his parents were Scottish missionaries since there are several preachers at least in the Ronaldson family. Since he is a cousin, somewhere along the line that I've not been able to establish yet, there is also a good chance that his parents were likewise.
I was looking for his military background and the fact that he had been the Surgeon General to the Allied Forces during the Boxer Rebellion (1870) because I felt those records would be the easiest to find. I was hoping that because of his position, I would find a biography about him. As of yet, I have not been able to locate such a record.
I will see what I can do on the birth records. Hopefully during that time frame there are not that many William Rutherfords who were born.