We all say we want our kids to be happy, only happy, and healthy, but we don't want that. We want them to be like we are, or better than we are. We as humans are very unimaginative in that sense. We aren't equipped for the possibility that they might be worse. But I guess that would be asking too much. It must be an evolutionary stopgap - if we were all so specifically, vividly aware of what might go horribly wrong, we would none of us have children at all.