The Mormon.org Blog has written this nice summary of The Family: A Proclamation to the World:
In 1995, leadership from The Church of Jesus Christ of Latter-day Saints (also known as Mormons) released “The Family: A Proclamation to the World,” a document outlining Mormon beliefs on families.
Its purpose is to clearly “proclaim that marriage between a man and a woman is ordained of God and that the family is central to the Creator’s plan for the eternal destiny of His children,” as well as define important beliefs about the family’s eternal nature, the sacredness of marriage, and parental roles and responsibilities.
What does it say?
In summary, we believe that all mankind was created in God’s image. We believe that He is our father, and as such, we are all heirs to eternal life with a divine nature and destiny.
We believe that God’s commandment to Adam and Eve to multiply and replenish the earth still applies today, and we believe that the powers of procreation are sacred and should be exercised between a man and a woman lawfully wedded as husband and wife.
We believe that husbands and wives have a sacred responsibility to love and care for each other, and to provide for, teach, serve and love their children.
We believe that marriage between a man and a woman is vital to God’s plan and that all children are entitled to a birth within the bonds of matrimony and a childhood within the walls of a loving, trust-filled home.
We believe that fathers are primarily accountable for the provision and protection of their families, and mothers are primarily responsible for the nurturing of their children. Both a father and a mother, however, should be committed to each other as equal partners, and circumstantial situations should be adapted to and accounted for.