|Merthyr Tydfil Garden of Remembrance. From Helen Rigby.|
According to her daughter Sarah Ann’s biography, Mary Howells Thomas joined The Church of Jesus Christ of Latter Day Saints (often called Mormons) on November 8, 1841, which would make her one of the very early converts in Wales as the first LDS converts in Wales were at Overton in 1840.  She was a member before she married David Thomas, and for several years before he was baptized February 15, 1849 by John Edmunds and confirmed February 16, 1849 by Joseph Davies and was ordained an Elder two days later, probably in the Aberdare branch as they were living in the Aberdare area when Isaac was born in 1850. 
The Aberdare branch was one of the early LDS branches in Wales and had been organized since April 6, 1844. Mary was a strong member of the Church and a faithful supporter of the missionaries. She had a great desire to immigrate to Zion with the many other Welsh Saints, and the family made preparations to go to Zion. However, before she could realize her dream, she died in 1860 of tuberculosis. The death certificate for Mary Howells gives the following information: Mary Thomas died 3 September, 1860 in Cwmaman, Aberdare, wife of David Thomas, Blacksmith. Cause of death is Phthisis (archaic term for tuberculosis) and disease of the heart. “X” The mark of John Howells in attendance, Canon Street, Aberdare. 
I found three accounts of this traumatic period in the life of David and his children, and because the details differ somewhat I have included them as they were written.
From an account filed with the Daughters of Utah Pioneers:
David Nathan Thomas had a wife and four children at the time he joined the Church. (Actually, the three younger children were born after David was baptized.) The wife, Mary Howell, was a sufferer of T.B. Since the doctors advised them not to make the long trip to America, they waited for fifteen years, hoping that the wife would get strong enough to make the trip to Zion in order to be with the Saints. During this time, their home was always open to the elders. Many found rest and comfort there. The family’s great wish for their mother was never realized. When David Nathan was ready to come, he made the trip with his four motherless children. 
When Sarah Ann, David and Mary’s third child, was in her seventies she recounted to her granddaughter some of the events of her life:
Her parents (David & Mary) were converted to the Latter-Day Saints Church by Mormon missionaries sent from Utah to South Wales. After their conversion, they were determined to go to Zion. By careful saving and selling what possessions they owned, and borrowing from the General Emigration Fund of the Church, they were able to pay for their passage. They did not, however, have money for traveling from Cwmaman to Liverpool, the seaport from which they would sail to America. There was no other option open to them, but to walk to this port. In the British Isles in normal weather, it rains more days than the sun shines. Thus it was almost certain they would have to travel in rain part of the way. The distance from Cwmaman —as the crow flies—as it appears on the map to Liverpool is about 125 or 130 Miles. Following the traveled roads and paths it may have been quite a number of miles farther than that. How long such a journey on foot with four young children would take, I do not know. This much I do know: That it must have been sometime in the month of March when they set out for they sailed for New York in April. Another sad development indicates that they had not traveled far from their home when Grandma’s mother, Mary Howell Thomas, became ill from walking in the cold rain that fell. A day or so later, she dies –somewhere in Glamorganshire, leaving a saddened husband and four, forlorn, bewildered children. Glamorganshire County is not a great distance—from the map it looks to be perhaps 15 or 20 miles—maybe less. At any rate the family had not traveled very far when this tragedy struck. “What did Grandpa Thomas do? What did he say?” I asked, touched and dismayed, for sadness had crept into Grandma’s voice in relating this part of her history.
“Just went on. We had nothing to go back to. Our tickets were already bought to America. So we walked on until we came to Liverpool and boarded ship with the other Saints.” 
In a biography of Mary Howells, David and Mary’s oldest daughter Margaret told about the death of her mother: 
She (Margaret) recalled that when she was about 10 or 11, [according to date on Margaret’s birth certificate, she would have been 15]; that she was alone in the house at the time with her Mother who was standing at the sink. Her mother fell to the stone floor of the kitchen. She (Margaret) ran out calling to the neighbors, “Mae Mam yn sal!” [“Mother is sick.”] The neighbors came and took a mirror off the wall and held it up to the mouth of her Mother to see if there was breath in her body, and then shook their heads, saying, “Mae hi wedi mynd.” [“She’s gone.”] 
She (Mary) was the member of her family who first accepted the Mormon gospel in South Wales. She had the missionaries to dinner nearly every Sunday and did convert her husband David Thomas, and their children, Margaret, Isaac, Sarah Ann, and Mary. Margaret said that the family had just joined the Mormon Church about the time their mother died, and that they were baptized in the river at night so the neighbors wouldn’t know they were Mormons. 
According to the recollections of David and Mary’s two daughters, Margaret and Sarah Ann, the family had already sold their possessions, bought their tickets, and were preparing to leave for Zion when Mary, the mother, died. Actually, it appears there were about 18 months between the death of Mary in September, 1860 and their departure from Liverpool on April 23, 1862.
Although there appears to be some differences in the retelling of this tragic period in their lives, the biographers agree that Mary joined The Church of Jesus Christ of Latter Day Saints in the early days of the church in Aberdare and that she was a devout and staunch supporter of her beliefs; that she converted her husband and children; that she saved and prepared to come to Zion, and that her husband and children carried on with the plan to come to Zion. It seems there were about ten or eleven years of hard work, sacrifice and saving to get ready to emigrate to America. Like many other LDS immigrants, David was able to borrow a portion of the money for his family’s passage from the Church’s Perpetual Emigrating Fund. 
 “Record of Members, 1879-1939,” St. Johns Ward (Arizona), St. Johns Stake (Arizona), Church of Jesus Christ of Latter-day Saints, Film 0002456, LDS Family History Library, Salt Lake City, Utah.
 Certified copy of death certificate for Mary Howells in the possession of Ann Marie Bridges, Monroe, Utah. Photocopy in possession of Helen Price Rigby. [See copy in appendix #1.]
 Anonymous, “Biography of David Nathan Thomas,” Daughters of Utah Pioneers.
 Virginia Dyches Nielsen, “A Brief History and Personal Memories of Sarah Ann Thomas Dyches.”
 Biography of Mary Howells, probably written by Delphia Despain, great-granddaughter of Mary Howells obtained from Delphia’s daughter, Betty Jean Despain Aagard, Ft. Green, Utah, February 2007.
 Welsh phrases, courtesy of Ron Dennis, retired professor of language at BYU; also group leader of a tour to Wales and Scotland which Jay and I took in 2002.
 History of Margaret Thomas Price by Delphia Rees Despain. Delphia was a granddaughter of Margaret and Richard Price. She and her sister and her mother, Mary Ellen Price Rees, lived with Margaret and Richard after her father, Nephi Rees, died. Obtained from Betty Jean Despain Aagard, Ft. Green, Utah in February 2007. Betty is now deceased.
 Names of Persons and Sureties indebted to the Perpetual Emigrating Fund Company 1850 to 1877, Richard L. Jensen,
Rigby, Helen. "A History of David Nathan Thomas and his wives, Mary, Adeline & Frances." Utah: n.p., 2011.