I once saw a Dutch documentary, it was about a Dutch-Jewish family - a man, woman and their child - who wanted to cross the border to Switzerland. The man was caught however by the Gestapo, but like a miracle, the woman and her son escaped and reached Switzerland. The man was later gassed in Auschwitz. The woman had written many letters about this period, but never said anything about it. She died in the 1950's. Her son was not aware of this suitcase full of letters. When he died in the 1990's, his son discovered the suitcase with all his grandma's letters, and by that also got the chance to look at the history of his family in the 1940's. Really interesting.