I’m sorry you misunderstood.
The living don’t marry the dead, the living stand in proxy for the dead who are then married for eternity to each other.
Lets say you and your wife/husband are Mormon converts, married before you join with 2 kids.
After one year, you both go to the temple and take out your ‘endowments’. This is where you learn secret handshakes, get a new name and take oaths (they used to be violent blood oaths but they have toned them down). Then you and your spouse are “sealed” to each other, this means that although you were married your marriage was for this life only, once you are sealed you are married ‘for time and all eternity’ meaning you will still be married in the afterlife.
Then you will have your kids ‘sealed’ to you so they will be part of the family unit in the next life as well.
After that, you and spouse decide to do the ‘temple work’ for your never mormon grandparents who died several years ago.
So you and your spouse (or someone else) is baptized in their name so they (after death) become mormon (but not counted as a memeber), then you and your spouse go through the endowment ceremony in proxy for them (as them using their names) to they know all the handshakes and take all the oaths and get THEIR new name.
Then you and your spouse are sealed or married for eternity in their names as well so THEY will be married in the next life, and then you will have your dad and aunt and uncle (only the ones that are dead) sealed to your grandparents as their children.
This is the main reason why Mormons are so obsessed with genealogy. They believe everyone who has ever lived HAS to have this work done for them in order for that person to get to the Celestial Kingdom (mormon heaven).
Is that any clearer?
i do have some mormon friends in utah - and i have nothing but respect for them
i did read a book whose author had left the lds church - it had some interesting insights into the marriage ceremony (and i am sure many other things) - but what stands out in my mind was dealing with death - and that a man must lift the veil from his wife if she is to enter heaven - and that she will be perpetually pregnant in heaven - and a few other things i’d rather not say here
i guess for an outsider, some of it seems odd since we were not reared in the lds church - they probably think the same of us
I never heard of Jesus doin’ any secret handshakes