I have one mom. I have 2 grandmas, and assuming that your mom and dad aren't brother and sister, you have two grandmas also.
No, the LDS church does not practice polygamy. No, the FLDS church is not affiliated with the Church of Jesus Christ of Latter-day Saints (LDS church).
The church has an official statement on polygamy which says this:
Today, the practice of polygamy is strictly prohibited in the Church, as it has been for over 120 years. Polygamy — or more correctly polygyny, the marriage of more than one woman to the same man — was a part of the teachings of The Church of Jesus Christ of Latter-day Saints for a half-century. The practice began during the lifetime of Joseph Smith but became publicly and widely known during the time of Brigham Young.
In 1831, Church founder Joseph Smith made a prayerful inquiry about the ancient Old Testament practice of plural marriage. This resulted in the divine instruction to reinstitute the practice as a religious principle.
Latter-day Saint converts in the 19th century had been raised in traditional, monogamous homes and struggled with the idea of a man having more than one wife. It was as foreign to them as it would be to most families today in the western world, and even Brigham Young, who was later to have many wives and children, confessed to his initial dread of the principle of plural marriage.
Subsequently, in 1890, President Wilford Woodruff, fourth president of the Church, received what Latter-day Saints believe to be a revelation in which God withdrew the command to practice plural marriage. He issued what has come to be known as the "Manifesto," a written declaration to Church members and the public at large that stopped the practice of plural marriage.
Today Church members honor and respect the sacrifices made by those who practiced polygamy in the early days of the Church. However, the practice is banned in the Church, and no person can practice plural marriage and remain a member.
The standard doctrine of the Church is monogamy, as it always has been, as indicated in the Book of Mormon (Jacob, chapter 2): “Wherefore, my brethren, hear me, and hearken to the word of the Lord: For there shall not any man among you have save it be one wife; and concubines he shall have none. … For if I will, saith the Lord of Hosts, raise up seed unto me, I will command my people; otherwise they shall hearken unto these things.”
In other words, the standard of the Lord’s people is monogamy unless the Lord reveals otherwise. Latter-day Saints believe the season the Church practiced polygamy was one of these exceptions.
Polygamous groups and individuals in and around Utah often cause confusion for casual observers and for visiting news media. The polygamists and polygamist organizations in parts of the western United States and Canada have no affiliation whatsoever with The Church of Jesus Christ of Latter-day Saints, despite the fact that the term "Mormon" — widely understood to be a nickname for Latter-day Saints — is sometimes incorrectly applied to them."
How I Personally Feel about Polygamy
I won't pretend that polygamy didn't happen in the early days of the LDS church; obviously it did. But there were lots of reasons and the bottom line is I dont know how those women, or those men, did it.
It is hard enough for a man to support one family, let alone several.
And I deeply admire the women who worked so hard to take care of their kids and support each other while their husbands were gone.
Our church today and in the past has really emphasized the importance of family and the roles of fathers and mothers and that their spouse and their children must be their number one priority. In fact, the LDS church has issued a Proclamation to the World on Family. (found here https://www.lds.org/topics/family-proclamation)
I don't know all the reasons why God asked the members of the early LDS church to practice polygamy but I know a few of the reasons. There were a lot of women joining the church; some of whom were leaving drunk, abusive husbands in Europe. Legally and financially and physically, it was impossible for these many single women to make the trip to Utah where they would be free from religious persecution.
As I said, I really admire these women for the sacrifices that they made in following what they believed to be true, despite the difficulties of the situation. I think it was easier to be someones 3rd wife, than to be no ones wife and have no man to take care of your kids. Obviously it is ideal that a mother and father take care and raise their kids in love. I'm just so glad that the time frame for polygamy was short and I think it served its purpose even though I don't know all of the details of its purpose (God knows so much more than I do!)
But honestly and realistically, I can't imagine sharing my husband Matt. The army already kinda acts as a second and third wife .