Gospel Topics Essays found onLDS.org – Mother in Heavenpublished on October 23, 2015.
It starts out by saying,
“The Church of Jesus Christ of Latter-day Saints teaches that all human beings, male and female, are beloved spirit children of heavenly parents, a Heavenly Father and a Heavenly Mother.”
Latter-day Saints believe the, human race lived in a premortal existence with Heavenly Parents and that all people are begotten spirit children of God.
One thing the essay doesn’t mention is the idea that there are plural mothers in heaven. However, it has been taught in Mormonism that God the Father is a polygamist.