From Today's news.
http://www.foxnews.com/science/2015/11/16/anne-frank-diary-now-has-co-author.html?intcmp=hplnws
The claim of an additional author (who was in fact always stated to be only an editor and compiler) has now extended the copyright even further.
Potentially of interest to editors. There is bound to be a law case relating to this.