A recent cold-case investigation might have uncovered who betrayed Anne Frank's family and turned them over to the Nazis, according to a new book. The Frank family hid for two years in the annex of a warehouse in Nazi-occupied Amsterdam before they were discovered in 1944 and sent to Auschwitz. Anne, who wrote her famous diary documenting their time in the annex, died one year later at age 15 in the Bergen-Belsen camp.