Bryan, George had posted the below information saying he died on a boat. Your information says he died in the hospital. Then your information says "thought dead". Does that meean his body was not there when his wife was there?

(S. F. Cox " . . . died of disease on board a boat between Van Buren & Little Rock, Ark. on or about the 28th day of December, 1862, . . . "*/ January 2, 1863 at Little Rock, his widow Mary Ann Cox filed claim for his pay and allowances

* Affidavit of Mary Ann)

You are correct on the wives names. Sarah Ann Cox was Fulkers wife. They had a daughter named Eliza Maryetta ( Mollie) Cox ( My GR GR Grandmother). I have searched and searched and I can not find out what happened to Sarah after Fulker died in 1863. I have a copy of a letter that Fulker wrote to Sarah just weeks before he died. She was living in Spring Hill township of Hempstead county. I can't find a trace of Sarah after this. She and her daughter seem to have vanished. I don't find them anywhere in the 1870 census. Mollie appears in 1879 when she marries Henry Hawakins Brown in Hempstead county AR. Our family story that has been handed down is that Sarah married one of Fulker's brothers. However I have found out that Samuel F.'s wife Mary married a Cox brother named Thomas E. Cox. There is another brother named James Cox that was in the war also that seems to have vanashed about the same time that Sarah ( Fulkers widow) did. I can't find out any information on James Cox.