Evidence from genealogical sources prove the Dennis family came to Utah in 1855. Sinia's sister, Talitha, was born in Iowa in September of 1854 and the parents had temple work done in the Endowment House in November of 1855. So they must have come on that season's emigration in 1855. Sina was rebaptised in the Lehi Ward on 1 April 1857. Her birth date is confirmed in this record. The 1860 census records her given name as "Lila." She married George Dixon Snell in 1863.
The inscription on her gravestone shows her given name as "Sinia." It also confirms her death date.