Son of James and Lydia Moon Clayton. His father died at Winter Quarters and his mother married John Clayton; both of these men were brothers of William Clayton. In the 1850 Iowa census Hyrum was in the household of his step-father--John. In Utah Lydia Moon Clayton married Thomas LaFlesh Munjar so Hyrum appears in the 1856 Utah census as Hyrum "Mungar" of Tooele. He died in Butte County, California and is buried there. "Hiram's" obituary from the Chico Enterprise newspaper may be found in his Find A Grave memorial.