We have a wolf, a lion, a jaguar, a mongoose, a tree, and a wall! So, yeah, I would have to say that non-human parts are possible!

As far as dealing with them...it may be better in some cases to deal with why they are needed, then to deal with them directly. For me/us, the wolf protects the littles at night...he patrols the hallways while they sleep. The lion is here because one little one wanted/needed a big, strong protector that would not leave her side (to watch over other littles for example). The jaguar prevents "dangerous/scary" ones from "getting out". The mongoose we aren't sure about yet, but may have to do with combatting snakes which have been said to be (in our case) RA related. The tree and the wall, we aren't sure, but I can think of many possible reasons that a wall would be useful!