This time she walked across the keyboard and deleted about 100 titles. Yikes!
and there isn't an undo function. Fortunately I had copied and backed up my PVD file about 3 days ago so I was able to recover things with just a few changes lost.
The point of this post is to highlight the importance of backing up your PVD files. Keep a recent copy available to recover from catastrophes or, in my case, CAT-astrophes. It only takes a few minutes and some day you'll be glad you made the effort.