Someone asked for LDS church sources for polygamy and polyandry in order to talk to their mom:

1)
The Swedish Rescue Fireside, audio and transcript
http://www.youtube.com/watch?v=j_2Ht4d9R5g

2)

http://en.fairmormon.org/Firesides/28_November_2010_-_Sweden/2

A FairMormon Analysis of: Questions Asked at 2010 Swedish Fireside


FairMormon-Answers- QUESTIONS

Response to questions about polygamy and polyandry

Question:
I have a difficult question. The time of Abraham, God reveals that.... it’s OK to have more than one wife....does the church believe that it was a teaching from God that he married women who had other men that were still alive, and even some apostles wives when they were away on missions?
One woman said the child that she bore she didn’t know if it was the child of Joseph or the child of, in this case, Orson Hyde....So that indicates that it was definitely not a spiritual marriage.
Short Answer:
Question: Did Joseph marry women who were already married to others?

Answer: Yes. (( ANSWER: YES ))


* There is no evidence these marriages were consummated. They were likely to bind families together to Joseph as a sealing ordinance.

Question: Does the church believe that polyandry was a teaching from God?

Answer: Based upon what we know about the goodness and compassion of Joseph Smith's character, it might be wise to suspend judgment about what we don't know about the practice.


I don’t know. I can’t say that Joseph Smith did anything that was unholy. I can honestly say that everything I know about him and his goodness and his compassion helps me at least suspend my judgment about what I don’t know. And polyandry is one of those things. I personally couldn’t live polygamy. And it’s something my wife couldn’t live. I’m so grateful that we came in a time when that wasn’t a commandment of God for us.

—Elder Jensen's answer to this question at the Sweden fireside


Question: Was Joseph sealed to apostles' wives?
Answer: Yes, in one case.


*Joseph was sealed to Orson Hyde's wife, Nancy Marinda Johnson Hyde.
Question: Did Joseph marry the wives of men on missions? Answer: Yes, in one case. No in all the others.

Joseph was sealed to Orson Hyde's wife Nancy after Hyde had been gone for nearly two years. Upon his return, the sealing was repeated with Hyde's permission.
In all other sealings, the husband was not away on a mission.
...

sorry I am unable to find the trhread that was asking for this information today.

And found this thread that addresses several sources and has church manual links also:


http://exmormon.org/phorum/read.php?2,1404314,1404916#msg-1404916

Can you believe this comment from a Mormon?