She and her family is in Iowa at the time of the 1860 Iowa census (enumerated August 7th). First documentation to place her in the Valley is a rebaptism performed in the West Jordan Ward on 21 October 1864. She likely traveled with her mother who is seen in West Jordan in late 1863, so she would have traveled between 1861 and 1863. Birth date is recorded in those records at the time of that ordinance. Many records list her given name as "Jemma."
Further research is needed to narrow the year of travel and identify the name of the company she traveled with.