The first thing you’ll want to consider when determining whether or not your bed space occupant is alive, is it’s origin.
When I say it’s origin, I mean where the bear came from. Where did you find it, buy it, or otherwise procure it. Was it passed down? Was it purchased from a conglomerate retail store? These are all very important questions to ask, for if you know a object’s origin, bear or otherwise, you can better understand it’s nature, supernatural or otherwise.
Of course in some cases, you aren’t able to answer this question for yourself. Often times a teddy bear is just there. This in itself can be a very telling sign. If the origin of a teddy bear somehow escapes your mind no matter how hard you think about it or who you ask, it’s probably because the bear had no origin beyond appearing out of thin air. Perhaps blending itself in with other long-owned but not often noticed items, slowly emplacing itself in your mind as a thing that has always been there.
Other origins that may be clues as to whether a teddy bear is breathing an unnatural life through its body include: Buying a common brand bear for cheaper at clearance because it has been “tampered with”; winning a bear at an unusual or especially worn-down carnival (perhaps winning a bear at any carnival would suffice to be suspicious evidence); purchasing a bear from a shady or unusual character in a shady or unusual place, possibly for free; finding an abandoned teddy bear anywhere. This means in a dilapidated house, in an alleyway, by some garbage bins, halfway stuffed in a storm drain (especially if it looks as though the teddy bear has managed to crawl some of the way back out), on your doorstep, in a dusty basement, in a rundown toy store, outside a rundown toy store, in the general vicinity of a rundown toy store; anywhere. A child never wants to abandon their beloved teddy friend, but if the bear is a stuffed sack of evil, there is a good reason that said bear is abandoned!
All of the above examples serve as strong indicators that your teddy bear is not as sleepy as you are when it comes time to rest your head.