Excerpt from Joseph Fielding Smiths ‘Doctrines of Salvation’: 1
“PROCREATION LIMITED TO CELESTIAL BODIES. Some will gain celestial bodies with all the powers of exaltation and eternal increase. These bodies will shine like the sun as our Savior’s does, as described by John. Those who enter the terrestrial kingdom will have terrestrial bodies, and they will not shine like the sun, but they will be more glorious than the bodies of those who receive the telestial glory.
In both of these kingdoms there will be changes in the bodies and limitations. They will not have the power of increase, neither the power or nature to live as husbands and wives, for this will be denied them and they cannot increase.
Those who receive the exaltation in the celestial kingdom will have the “continuation of the seeds forever. They will live in the family relationship. In the terrestrial and in the telestial kingdoms there will be no marriage. Those who enter there will remain “separately and singly” forever.
Some of the functions in the celestial body will not appear in the terrestrial body, neither in the telestial body, and the power of procreation will be removed. I take it that men and women will, in these kingdoms, be just what the so-called Christian world expects us all to be — neither man nor woman, merely immortal beings having received the resurrection. “
|1||Doctrines of Salvation. vol. 2, pg. 287-288 – https://archive.org/details/Doctrines-of-Salvation-volume-2-joseph-fielding-smith|