Hiram Harvey was not married yet in 1860 according to Lamar Co TX Census. He was 23 years old and living in the household with his father at that time. His occupation was listed as a teamster.
He is listed in the Texas Civil War records as having served in the Texas Confederate Army during the U.S. Civil War, having enlisted in Lamar Co. TX.
His marriage record was found in Lamar County Marriages, Book 3, page 175.
He is listed on the 1870 Greenwood Co. KS Census records with his wife and two children, living in Fall River, just a few houses from that of his aunt, John and Lydia (Clement) Gage, and their children. Also living in the household of Hiram Harvey was a Henry Clement, age 14. It is believed that Henry is probably a child of Letha and was adopted by Harvey after their marriage.
Harvey and Letha are also listed in the 1880 Wise Co. TX Census records living near his brother William Clement and Etheldra.