I've read about Indigo Children, Crystal Childrean, I believe another is Rainbow and there are a few others. I haven't heard of such prophecy, it sounds like something you really want to check the sources and credibility behind. From what I understand there have been multiple crystal children as it is, however this prophecy you propose suggests they aren't "real". I can provide some of the texts I've read from, sounds like you're a little hazy on what these people are. While it is true that people of this image are classified as something special, different, and with their own contributions of greater humanity I don't see why such a prophecy was even bothered with. It's like saying, "One day someone might cure cancer, one day someone might kill a bunch of people, whatever happens we're calling them the real Pancake. All you other Pancakes are just imitating."