Modern science has proven numerous times that there are things that we cannot see, hear or experience that do indeed exist. For example Albert Einstein theory E=MC2 states that matter is compressed energies. We did not believe this until we got the technology to see that he was indeed correct. Atoms were seen with this theory, and the Atomic Bomb was created.
Recently, using the super string theory ( A theory stating that all particles vibrate at a certain frequency and when one particle vibrates the same as another it becomes that particle) we have been able to teleport an atom between dimensions at least ten were discovered.
Proving we do not know everything about the universe.
You must ask yourself could you possibly know everything about the universe in order to disbelieve in Fairies?
The possibilities are endless.