DHO refers to heavenly parents theology.
Dallin H. Oaks, "Priesthood Authority in the Family and the Church," General Conference Address (October 2005), accessed May 26, 2021
The theology of The Church of Jesus Christ of Latter-day Saints centers on the family. Our relationship to God and the purpose of earth life are explained in terms of the family. We are the spirit children of heavenly parents. The gospel plan is implemented through earthly families, and our highest aspiration is to perpetuate those family relationships throughout eternity. The ultimate mission of our Savior’s Church is to help us achieve exaltation in the celestial kingdom, and that can only be accomplished in a family relationship.