In the Church of Jesus Christ of Latter-day Saints, when was it first formulated that there will be opportunity for marriage after death?

One doctrine that has been consistently taught in the Church of Jesus Christ of Latter-day Saints is that, if people had accepted the gospel but didn't have the opportunity in this life, they will still be saved and be able to receive all the blessings of the gospel. This general idea goes back to at the latest Joseph Smith's vision of the celestial kingdom, where he was surprised to see his brother who died before the restoration of the church. D&C 137 > 5 I saw Father Adam and Abraham; and my father and my mother; my > brother Alvin, that has long since slept; > > 6 And marveled how it was that he had obtained an inheritance in that > kingdom, seeing that he had departed this life before the Lord had set > his hand to gather Israel the second time, and had not been baptized > for the remission of sins. > > 7 Thus came the voice of the Lord unto me, saying: All who have died > without a knowledge of this gospel, who would have received it if they > had been permitted to tarry, shall be heirs of the celestial kingdom > of God; > > 8 Also all that shall die henceforth without a knowledge of it, who > would have received it with all their hearts, shall be heirs of that > kingdom; > > 9 For I, the Lord, will judge all men according to their works, > according to the desire of their hearts. Now, the covenant of marriage is seen as vitally important to receive the highest blessings in the celestial kingdom (D&C 131 ). LDS perform proxy sealings in the temple for those who were married in life but not in the "new and everlasting covenant" that is eternal marriage. With regard to those that, for some reason or another, did not have the opportunity to marry in this life, no proxy marriages are (kind of obviously) performed. Yet it has been consistently taught since at least Lorenzo Snow that there will be opportunity for those eventually (in the millenium I suppose) to be married. https://www.churchofjesuschrist.org/study/manual/teachings-of-presidents-of-the-church-lorenzo-snow/chapter-9-sacred-family-relationships?lang=eng&id=p8#p8 > People who have no opportunity of marrying in this life, if they die > in the Lord, will have means furnished them by which they can secure > all the blessings necessary for persons in the married condition. The > Lord is merciful and kind, and He is not unjust. There is no injustice > in Him; yet we could scarcely look upon it as being just when a woman > or a man dies without having had the opportunity of marrying if it > could not be remedied in the other life. There would be injustice in > that, and we know that the Lord is not an unjust being. My sister > Eliza R. Snow, I believe, was just as good a woman as any Latter-day > Saint woman that ever lived, and she lived in an unmarried state until > she was beyond the condition of raising a family. … I cannot for one > moment imagine that she will lose a single thing on that account. It > will be made up to her in the other life, and she will have just as > great a kingdom as she would have had if she had had the opportunity > in this life of raising a family. (Quote from 1899, shortly after becoming president of the church in 1898) Was Lorenzo Snow the first to formulate the doctrine this way? Surely all the building blocks were already there even in Joseph Smith's time. Please correct me if I am wrong in this, but I assume none of the standard works go into this topic, so what we have here is an example of doctrine defined by "the modern-day prophets consistently taught it".