On Christmas Eve 1842, the first husband of Susannah's mother, George Sweeten died, leaving his widow the care of two small children, Robert and an older sister Margaret.
Missionaries of a strange new faith visited the little Canadian settlement and the message they brought was welcomed by the young widow and her parents, Robert Gardner and Margaret Calinder and her brothers and sisters. Soon they were all baptized and became members of the Church of Jesus Christ of Latter-day Saints. Two younger brothers were soon ordained Elders and were set apart to preside over the newly formed Canadian branch.
In 1844, Mary Gardner Sweeten married Roger Luckham, a young Englishman. To their union were born two daughters, Mary, who was born in their Canadian home, and Susannah, who was born in Salt Lake City in 1848.
A desire to gather with the main body of the saints came upon the members of the Canadian branch and led by Archibald and Robert Gardner, they set out for Nauvoo, Illinois. When they reached Nauvoo they found it a deserted city, with evidence of every side that the Saints had fled in haste. They caught up with the last of the line and continued on to Winter Quarters where they, with others, spent a winter of suffering and hardship.
In October 1847, they arrived in the Valley of the Great Salt Lake. William Gardner, concerned with the business of establishing mills in this new country, had gone north into Cache Valley and had started building a mill at Gardner's Creek, two and one-half miles South of the present community of Mendon.
In 1856, Mary and Roger Luckham and their family paid them a visit and were favorably impressed with the country and decided they would return and make their home there as soon as they could. They were not able to realize their ambition, for with the summer of 1857 came news of the approach of Johnson's Army and the order to Move South. During this move, Susannah's mother suffered from exposure and as she had not been very strong since her illness while en route to Utah, this additional exposure led to her death June 12th, 1858, at Spanish Fork, Utah.
The next spring, Roger Luckham with his two daughters, Mary and Susannah, and his stepson Robert, now a lad of eighteen, arrived where the city of Mendon now stands.
The following is from the journal of Daniel B. Hill Richards: About May 1st, 1859, Roger Luckham, his daughters Mary and Susannah, and his step-son Robert Sweeten, two Englishmen, Charlie and Alfred Atkinson and their families, arrived where Mendon now stands.