McCaslin married Pennina Jane Smith on Nov 28, 1809 in Johnston, North Carolina. The Frost family continued to live in North Carolina until sometime between 1814-1816 when they moved to Knoxville, Tennessee. They continued to live here for many years.
Samuel, McCaslin's oldest son, while on a trip to secure work up north was introduced to missionaries of the Church of Jesus Christ of Latter-day Saints. Samuel was later converted to the Church and brought the newfound religion to his family who were also converted, along with their neighbors, the Bright family. Sometime before 1840, the Frost family moved to Jefferson County, Iowa. They participated in church activities up until the time of the assassination of Joseph Smith in 1844.
The Frost family moved deeper into Iowa to keep their distance from the mobsters that were harming the Saints. They moved to Fremont, Iowa sometime before 1850. McCaslin joined the Philemon C. Merrill Co. on June 5, 1856 to move west, and arrived in Utah on Aug 13.
It is unknown what McCaslin did while living the first part of his life in Utah. McCaslin moved to Richmond sometime before 1870.