Giordano thanks for your post.
In my opinion we can do a brief search on the Internet about the diary and come up with evidence either way. I think the challenge is to read the book with critical thinking skills and come to our own conclusion. I say this because none of your points in defense of the diary would I challenge, but I do challenge the diary based on Annes comments, about the need to be so silent, that they couldn't even cough at night, and yet they have constant noisy quarrels, use daily a noisy vacuuming cleaner, chop wood and have smoke come out the chimney at night. This and many other points make me using my independent thinking question how much of the diary was written by Anne Frank.
Anyway under copywriter law " The Diary of Anne Frank" should have became under the public domain in January 2016. Oh I say should, it's now considered that Otto Frank is an editor. Well that makes a bizarre argument, surely editing a book,especially a personal diary, shouldn't effect the authorship. Not unless it was co-written in my opinion.
The Rebel.
p.s Simon I apologise for my atrousious spelling and thanks for bringing the matter to my attention.