After all, nobody can see the dead but Cole, so as far as the world is concerned, the kid is just a constantly tense, antisocial and frightened young boy who occasionally enjoys writing horrible things in crazy scribbles on paper, lying about stealing, screaming at teachers and wearing his dead father's wristwatch and reading glasses sans the lenses.
The first hipster.
So it only makes sense when psychiatrist Malcolm Crowe (Bruce Willis) comes lurking around to try to help Cole deal with whatever the hell is making him so creepy.
During the film, Malcolm finds out about Cole's problem with the dead, and helps him slowly learn to deal with it by listening to what they have to say as opposed to freaking out all the time. He even escorts Cole on a bus to a girl's funeral, where he helps the little dead girl put her mother in jail for poisoning her. In the end, Cole finally 'fesses up to his mother and starts to heal psychologically.
Oh, and Bruce Willis is really dead the whole time, which you probably already knew and if you didn't, then ... well, you don't exist. Anyway this twist that everyone loved so dearly masked a pretty important detail in this film: If Bruce Willis was dead, then as far as Cole's mother knows, he never got any help with his psychological issues.
Ah, this kid's got nothing a little Ritalin can't fix.