Hindsight is 20/20. Looking backwards after someone's personality has developed, you can observe clear benchmarks that make their future seem obvious. But at the time, while the plot is still unveiling itself, there's no way to tell what the outcome of anyone's life story will be. You don't really know if a baby's going to grow into a saint or one of the world's most evil people.
The children pictured here all grew up to be some of history's most evil individuals. Looking at their young faces, you'd never be able to guess their fates, or the fates of their victims.