Yes, I had stumbled on the rest of what the LDS spokeswoman had said and stand corrected—to a degree. If we want to approach this fro a doctrinal point of view, the real conflict for me is that the Jesus and Satan as brothers idea equates Jesus and Satan while, I believe, (and it is a very common point of orthodox Christian doctrine) that Jesus and God the Father (along with the Holy Spirit are one and the same, They/He alone eternally pre-exist.
Not really, we are all spirit siblings. Satan and his followers were cast out and never received bodies and will not be resurrected.
The rest of us came to earth, receive a body, are tried to see if we have faith and are obedient, die and are resurrected, and then are judged and rewarded according to our judgement.
Christ was born like us to a mortal body. His biological father is our Heavenly Father and thus Jesus is the Son of God, and the Only Begotten. He was then offered as a pure sacrifice to atone for our sins. In Gethsemane and on the cross, he prayed to his father.