To the commenter who asked about the LDS doctrine that mother's whose child dies in youth will be able to finish raising them after the resurrection:
It is funny you should ask this right now. I just posted a comment on our angel blog to a mother who felt the same as your friend. In an effort to save time and avoid carpal tunnel :) I will just copy my comment here.
On the LDS doctrine of raising kids after the resurrection: First, you are right to think of your child as an adult. His spirit is a mature adult spirit. All of ours were before we were born and they all return to that state after we die. Your child, however, when he is resurrected will be rejoined with his body as it was when he died. Meaning, he will only be a few months old. He has no need to progress in all the spiritual ways that the rest of us do. But he cannot become like our Heavenly Father fully without the full development of his body.
I don't know what it is going to be like to raise such a child in such a time and with a resurrected body. Maybe they will be teaching us spiritual things from their cribs. I don't know. Maybe they will, like Jesus who was perfect, still have to grow mentally and emotionally as they age. But I trust that raising our children in that time will be sweeter than I can now understand or realize. I trust that it will heal all the hurt to our hearts. Somebody will have to raise each child who has died in their youth. These spirits will need to take the time to grow physically so that they can be like our Father. This will not be holding them back. It will be helping them progress.
In my case, Camille passed away just before she started talking. She was just beginning to understand and follow simple directions. I feel like I did so much of the baby work of no sleep and feedings and never got to the really rewarding part of hearing her call my name or tell me she loved me. I want that. I look forward to the day I can finish the work I started by bringing her into this world and raising her for the 14 months we had her. I believe strongly that this time raising her will be one of the sweetest experiences of my existence.
It is hard to imagine how we will feel then. But it is only important that we live worthy of any blessing we may then desire and that is ours for the having.
Hope that helps you and/or your friend understand this a bit better.