If you know anything about the LDS church, you know that we have a strong focus on family. Families are essential to God's Plan of Happiness for all of His children. Families are essential for our spiritual progression through this life. The world is very willing to teach children all sorts of things. Many things kids can learn in school or on the playground are not exactly in line with the teachings of Jesus Christ. Profanity, pornography, and downright blasphemy run rampant through our society today. Without parents teaching moral values in the home, there'd be nowhere to learn them.
I know that God lives and loves us. He has made it possible for us to stay together as a family forever. I know this to be true. God's priesthood is restored.
For more on eternal families see http://www.youtube.com/user/MormonMessages#p/c/4E784EC0770935C0/0/0J-_f4oRuWI