This is cross-posted to A03 & Tumblr under Clockworks Apprentice.
Ghosts never remember their deaths.
His parents had touched on it in their own research, for years they wrote papers on it being such a contributing factor to a ghost in the first place and why many could not just 'move on'. He never really put much faith into it, considering most of the things he had learned about ghosts later never quite matched up his parents' papers. Sometimes they came close and it was the times that they came close that actually made him worry about how much they were actually secretly right about.
But the more ghosts he fought - the more he met, the more he befriended - the more he found out that maybe what his parents said was right. At least, that one section was.
Danny first suspected this when he fought Poindexter; the ghost remembered Casper High, to the point his own lair created it, but when it came to the rest of the city? When it came to how he died? Danny learned the hard way that ghosts don't like those types of questions (this also set back all the progress he made with Poindexter as his ally).
The other ghosts had the same sort of reactions to his questions until he just learned to be quiet - and like hell, he'd ask Vlad.
Danny plops down his bed with a deep sigh.
All he wanted to know was why he couldn't remember the night of his accident.