What is the "lost generation" from the era ? where did the term come form?

The lost era is when you loose a era jk but it is the darkest era in the history

Anne frank was a very difficult person because she would never listen to her moms sometimes her dad even though he was her favorite and in times like that it would make it harder for there parents and other people in the annex to deal with her and since they were just stuck in there the couldn’t do anything but grounding her but even that didn’t work. hope that :