After some test, dwarves that die from old age raise from the tomb.
Ghost with 200 years; over the limit 170 years, the maximum lifespan of a dwarf.
I don't make test about ghost child growing to adult, or ghost reaching the max age date.
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From the wiki:
Ghosts may disappear suddenly, and if they do, their entry in the Dead/Missing list will disappear as well. When they are put to rest in this state, their entry will reappear.
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The ghost don't disappear, but moving between floors, out of dwarven vision cause the game to "lost track" of the ghost (using F:follow).
Using DFHACK reveal solve the problem, and the game don't lost track of the ghost (until some announce need the attention).
Elite Marksman ghost go to the barrack, and planter ghost go to meeting hall. I don't know the effect of profession in the ghost behavior.
I have some suggestion about old age. I found this post in reddit about ghost found dead of dehydration.
https://www.reddit.com/r/dwarffortress/comments/6azer1/ghost_found_dead_of_dehydration/If a Dwarves is dead of old age, the ghost appear, and the corpse is found, the game report "Ghostly Urist is dead from old age."
If the ghost is out of view (and out of units list) somebody can think that the ghost die from old age.
As result, i see that ghost/slabs/coffins is increasing in the fortress.