These are two creatures I know little about. I would like to know more about each, and am hoping that someone could tell me a little about one or the other - or both. What I do know about beldams is that they are a kind of witch, and that Neil Gaiman featured one in his children's novel Coraline. That's about it. As for changelings, the only thing I know about them as that they are a creature which switches their newborn young with our newborn young, so as to be raised in a human family - meaning they look human, or can look human, and thrive on a human upbringing. Again, any information on one or both would be greatly appreciated.