We believe that everyone is a spirit child of God (Acts 17:23-31). So yes, we're all spirit siblings. And history has seen plenty of siblings who turned out very different.
The Bible never said that God DOESN'T have a Wife. And it makes it pretty clear that a man is incomplete without a female partner. In whose image do you think God created women?
The Book of Revelation is pretty supportive of the doctrine that in the afterlife, after the resurrection and our return to Heaven, we can progress to our full potential, becoming gods. After all, offspring grow to become like their parents.
The Church of Jesus Christ of Latter-day Saints worships the Father and the Son (Jesus). We believe in and study the New Testament of the King James Bible. We strive to obey the Ten Commandments, attend church on Sundays, and show compassion, charity, and forgiveness throughout the week. So yes, we're definitely Christians.