March 1842 - Joseph Smith (Age: 36) married Patty Bartlett Sessions (Age: 47), who at the time was married to David Sessions. She is the mother of Sylvia Lyon.
"Patty Bartlett was born and raised in southwest Maine. Speaking of Patty’s Father and her upbringing, her oldest child, Perrigrine wrote: “[her Father] made no pretentions to religion and never belonged to any sect he was a very liberal man to the poor and was honest and upright in all his Deportment and taught his children to work and always to speak the truth”" (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 172)
"On June 28, 1812 Patty married David Sessions. They stayed in Maine and “bought land and made a farm built a log house and a large fraim barn...my husband by his industry on his farm and with his mills And by keeping a public house procured considerable wealth”. Patty and David had seven children only three of which lived into adulthood." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 173)
"While in Maine, Patty was trained as a midwife by her mother-in-law. Later, as a midwife in Illinois and Utah, Patty would deliver nearly 4000 babies." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 171)
"In August 1833, Patty came into contact with Mormon missionaries. Again, Perrigrine wrote, “And as soon as my Mother herd she believed and she was baptized and Confirmed into the Church of laterday Saints...” Apostles Brigham Young and Lyman Johnson later visited and “the gathering of the Saints was taught and preperations began to bee made to remove to Zion...we began to dispose of property as my Father and I had considerable.”" (In Sacred Loneliness: The Plural Wives of Joseph Smith pgs 175,176)
"The Sessions spent a year in Missouri and then settled in Nauvoo. There, Patty wrote in her journal: “I was sealed to Joseph Smith by Willard Richards March 9 1842 in Newel K Whitneys chamber Nauvoo, for time and all eternity...Sylvia my daughter was presant when I was sealed”. Patty was 47. Her daughter Sylvia had married Joseph a month earlier on February 8. It is unclear if Patty’s first husband, David, was aware of the marriage." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 179)
"After her marriage to Joseph, Patty continued to live with David. Three months later, he left on a mission to his former home state of Maine. Of the occasion, Patty wrote in her journal, “He left me alone, and I am very lonesome.” Two months later she wrote that she was “making shirts for Joseph.”" (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 180)
"Patty’s duties as Joseph’s plural wife included approaching and educating prospective wives, serving as a messenger and go between, and acting as a witness at the wedding ceremonies of Joseph and the other plural wives he took. Patty continued in this role until Joseph’s death in 1844. Patty and David later left Nauvoo for Utah with the other migrating Saints." (In Sacred Loneliness: The Plural Wives of Joseph Smith pg 179)
Source Material: http://wivesofjosephsmith.org/10-PattyBartlettSessions.htm
