You seem to think that because your brother may have turned into a horse theft, that that somehow reflects badly on how you led your life. We are all God’s children. Some turn out well some turn out not so well. Lucifer turned out badly and was cast out and took 1/3 of our brothers and sisters with him never to have the chance at physical bodies. We that are here ,while not perfect, did not rebel and therefore come to earth.
Well, the white ones of us, at least. The black ones stayed neutral, and were punished by being incarnated as blacks. (Mormons really believed that, at least before it became politically delicate to do so).
I’m sorry. Based on the Bible, I reject that belief as gross error. Jesus is now, and always has been infinite and eternal God Almighty. He has never been anything less than that - even when he walked the earth.
Lucifer is a finite, created being. He is not the "brother" of Jesus - spiritual or otherwise.