In the family plot fo the Haunted Mansion is a tombstone bearing the epitaph:
Master Gracey, laid to rest;
No mourning, please, at his request
There is, however, a small problem with that tombstone -- no one remembers who Master Gracey was. Well, the Master Gracey of the tombstone, that is. At least four persons went by the name of Master Gracey, since in the 19th century, “Master” was the term by which young adults of noble birth would be referred to (meaning all male Graceys were once called “Master Gracey” at some point).
The two main candidates (selected thanks to scientifically determined datation for the tombstone itself) are the Aging Man, Dorian Gracey, and the Ghost Host, Vincent Beauregard Gracey. Dorian was called Master Gracey all his life in the traditional, formal meaning described earlier in this page, thanks to his never-aging looks. Vincent, meanwhile, was often referred to as the “Master of Gracey Manor”, and has also been called Master Gracey on occasions because of this title.
The most likely of the two is probably Dorian, as “Master Gracey” for the Ghost Host was always an incorrect nickname that no one in his sane mind would put on a tombstone. Then again, the tombstone-designer of the family graveyard was clearly not a sane man, judging from the idly humanistic epitaphs he kept carving on them, so identifying a man by his nickname on the tombstone cannot be put past him. On the “Ghost Host” hypothesis's behalf, the epitaph also states that this Master Gracey asked not to be mourned, which sounds very much like a Vincent Gracey thing to say, given how Lord Gracey always expected to come back as a ghost and didn't consider death in any final sense.
APPENDIX: The Rose
For years on end, every morning, a fresh red rose would be found atop the mysterious Master Gracey tombstone. Nobody quite knows who put it there; some assume it is Gracey's forlorn bride (whichever of the Attic Beating Heart Brides that would be) who'd put it there; others say it is the Mansion's living Butlers and Maids who put it there as a sign of respect for their deceased boss (if it is the Ghost Host's tombstone) or a homage to a beloved and romantic departed's tragic demise (if it is Dorian's). Hundred more wild theories have surfaced, none any more or less plausible than those two.
Whatever the real reason, the living Disney Imagineers have recently decided to put an end to these flowery shenanigans; they don't care for the truth about this tomb all that much, but what they do care about is that, if it is the Ghost Host's grave as most guests assume, it just won't do for the foreboding master of a haunted house to appear to be a romantic Prince Charming. Make no mistakes, the roses keep surfacing, but Disneyland employees are instructed to take them away and throw them in a dump before the guests arrive.