Mysterious Sound in game - Anyone know what this is??

I went into my game and checked out my vamp-no sound.

I then went and made two new vamps each with differing weaknesses. I thought it may relate to undead aura or eternal sadness. However, no such luck :( .

@bebasims i love it too, just creepy lol. I even made my hubby listen to it and he didn't know what it could be.

I look forward to finding out what it is. Good luck!