September 1843 - Joseph Smith (Age: 37) married Melissa Lott (Age: 19).
"By June of 1842, the Lott family, including daughter Melissa, were living and working on the Joseph Smith farm just a few miles southeast of Nauvoo. Melissa’s father, Cornelius, managed the farm for the Prophet Joseph. This same year, eighteen-year-old Melissa moved to Nauvoo and lived in the Joseph Smith home, most likely helping with the children and household chores. Joseph III, was one of the Smith children Melissa would have cared for. He remembers Melissa was, “a tall, fine-looking woman with dark complexion, dark hair and eyes. She was a good singer, quite celebrated in a local way. I have heard her sing at parties and receptions in private home [and] on the stage where theatrical performances were given...”" (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 597)
"In June of 1843 Melissa was back at home living on the farm with her parents. Near the end of the month, Eliza R. Snow, Elvira Holmes, Elizabeth Durfee and Elizabeth Whitney visited the Lott farm. Eliza, Elvira and Elizabeth D. had married Joseph Smith a year earlier. Elizabeth W. was the mother of another one of Joseph’s wives, Sarah Ann Whitney. As a “Mother in Israel”, Elizabeth Durfee previously had an influential role in preparing the Partridge sisters to accept a plural marriage proposal from Joseph. Perhaps these women now helped prepare Melissa in the same way." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 597)
"By Fall of that year, Melissa had agreed to wed Joseph and they were married on September 20, 1843. Melissa’s parents stood witness at the ceremony. Melissa later recalled the wedding vows, “You both mutually agree to be each other’s companion, husband and wife, observing the legal rights belonging to this condition, that is, keeping yourselves wholly for each other, and from all others during your lives." Joseph’s wife, Sarah Ann Whitney, remembered similar vows, with an exception for Joseph who, of course, had many other wives: "...reserving only those rights which have been given to my servant Joseph by revelation.""(In Sacred Loneliness: The Plural Wives of Joseph Smith pgs 348,597,598)
"On the same day that Melissa married Joseph, her parents, Cornelius and Permelia, were sealed together for eternity. As with the parents Sarah Ann Whitney, and Helen Mar Kimball, perhaps this was a reward for giving their daughter to Joseph in marriage." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 598)
"Melissa described the contrasting elements to her and Joseph’s relationship, “I did not go to church with Joseph Smith, was never seen on the streets or in public places with him as his wife during his lifetime”. However, Melissa said they did share intimate moments, and that she was Joseph’s wife, “in very deed”. The following winter, Melissa returned to the Smith home to live. She continued to help with the Smith children. Joseph III, Fredrick and Alexander, attended the same school as Melissa, and she would escort them to school and back. In the Summer of 1844 Melissa was widowed when Joseph was killed in Carthage." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 598)
Source Material: http://wivesofjosephsmith.org/32-MelissaLott.htm