July 1843 - Joseph Smith (Age: 37) married Desdemona Fullmer (Age: 32).
"As a thirteen-year-old girl, Desdemona Fullmer remembers studying various churches and praying to know which one to join. On one occasion as she prayed she fell to the ground unconscious. For several hours she laid there, as if dead. She wrote, “Their was a voice said to me stop yet a little longer. their is something better for you yet...so I stopt till I heard the laterday santes preach the gosple I joined them soon after.”" (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 577)
"Some ten years later, in 1835, the Fullmer family obtained a Book of Mormon. They spent time reading it aloud together. Desdemona’s brother, Almon remembers, “it provoked mirth [amusement] since it so often came to pass. It riveted, however, a conviction of its truth upon our minds.” Desdemona was baptized a year later and soon gathered with the church in Kirtland and later in Missouri." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 579)
"In Missouri, Desdemona witnessed many of the persecutions suffered by church members. In spring of 1839 a mob came to the Fullmer home and demanded that they leave. Desdemona bravely replied, “we have no teem or waggon. we may as well dye in the house as a few roods from it. so they said hell let us go.” Soon, however, the Fullmers were forced to leave for Illinois." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 580)
"According to the Nauvoo 4th Ward records, in the spring of 1842, Desdemona was living in Joseph Smith’s home. She probably knew Emily and Eliza Partridge and Elvira Cowles who were also living there at the time. Some time before the spring of 1843, Desdemona moved out of the Smith home." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 580)
"Desdemona married Joseph Smith in July of 1843. As Joseph continued to secretly accumulate wives, his first wife, Emma, struggled with polygamy. Perhaps Desdemona experienced, or maybe only feared, the anguish of Emma discovering her and Joseph’s relationship. She recalls the resultant anxiety, “In the rise of poligamy i was warned in a dream Amy [Emma] Smith was going to poisen me.” Desdemona was not poisoned and remained Joseph’s wife until he was killed in June of 1844. In 1846, before leaving for Utah, Desdemona had her sealing to Joseph re-performed in the Nauvoo temple." (Mormon Enigma: Emma Hale Smith pg 165; In Sacred Loneliness: The Plural Wives of Joseph Smith pgs 581–582)
"Desdemona would marry twice more in her life, but neither marriage endured. When Desdemona was in her late fifties, she wrote a short autobiography and delivered it to the Church Historian’s office where it could be preserved. In it, she wrote, “I want to write a short history of my life the more particuler part that I think will do the youth som godde [good] and those that come into this church not having the same experience that I have had.” Desdemona died in 1886 when she was seventy-six and was laid to rest in Salt Lake City as “Desdemona Fullmer Smith”." (In Sacred Loneliness: The Plural Wives of Joseph Smith pgs 584–585)
Source Material: http://wivesofjosephsmith.org/30-DesdemonaFullmer.htm