Just remember:
"When did Mormon polygamy start?
According to historical records, Mormon founder Joseph Smith first taught plural marriage as early as 1831. However, he did not start practicing it until around 1835. See: Joseph Smith's Polygamy Timeline Chart.
The practice remained very secret until the official church announcement on polygamy in 1852. Top Mormon Church leaders Brigham Young and Orson Pratt introduced the doctrine at a special church-wide conference in Temple Square, Salt Lake City, Utah.
Did early Mormons marry and have sex with teen brides, like the FLDS and RLDS today?
Yes. According to church history, Mormon Church founder Joseph Smith married eight underage girls, including one 14 year-old, two 16 year-olds and his own foster daughters. These marriages were not normal for the 1840s, especially to a man in his thirties that was already married."
http://www.i4m.com/think/polygamy/polygamy_summary.htm