I have used CC, I think it is a very quick and effective way of dealing with sleep problems, but I was wondering if there was any research done into its long-term effects. My SIL is a child psychologist and she is dead against CC, so I wonder whether it is because of research she may have seen. I don't want to ask her about it because our babies are only 7 weeks different in age and discussions such as these are just not worth the hassle IYKWIM.