Jesus and Lucifer are brothers 

Bruce McConkie wrote in Mormon Doctrine, pg. 192;The devil (literally meaning slanderer) is a spirit son of God who was born in the morning of pre-existence. (D. & C. 76:25-26.)

Milton R. Hunter, The Gospel through the Ages, pg. 16:  “The appointment of Jesus to be the Savior of the world was contested by one of the other sons of God. He was called Lucifer, son of the morning. Haughty, ambitious, and covetous of power and glory, this spirit-brother of Jesus desperately tried to become the Savior of mankind. At the great council he proposed a new plan of salvation, event, the Lord revealed the following to Moses…

President Joseph Young said in Journal of Discourses, vol. 6:208;Who is it that is at the head of this? It is the Devil, the mighty Lucifer, the great prince of the angels, and the brother of Jesus. He left the province of his Father, and took with him a third part of his Father’s kingdom, and there was no other alternative but to banish him. God would have saved him if he could; but he could not. Lucifer and all his host went away to themselves…”

Also see Moses 4:1-6; Abraham 3:22-28

Hebrews 1:5; “For unto which of the angels said he at any time, Thou art my Son, this day have I begotten thee? And again, I will be to him a Father, and he shall be to me a Son?”

There are countless places in the works of LDS doctrines that touch on the subject of Jesus and Lucifer being brothers.  While it is an offensive thought to the Bible believing Christian; this is reality for the members of Mormonism.  We’ve only listed a few examples here and have provided the location of where you can read the various sermons in full.