They were treated poorly because of the same reason the Nazi's treated adult jews; it was because of their heritage. After they were sent into camps, it did not matter how old they were, no one was spared of his wrath.
If you want to know exactly what happened to them with great visuals, I suggest plugging "Children of The Holocaust" into YouTube and finding a great visual explanation to go along with your research.
Because they did not obey the voice of the LORD their God but transgressed his covenant, even all that Moses the servant of the LORD commanded. They neither listened nor obeyed. (I think that will be the answer to your question)
Well one reason is that it was to divide Berlin from 1961 to 1989.
Hope I Helped!
