Nope... 70 yrs old, no facebook, no email, not even a computer at her house. So no way the thieves did any kind of online snooping beforehand.
Sorry to hear this. The violation of your folks home will be the lasting legacy. Following along the lines of those warning about giving too much away. You can never be too careful. Reading this article and looking at the comments I am surprised in the number of respondents stating the store this and that at home. You don't need to be paranoid to see the danger of a few clicks through to your "linked" social media profile and more personal information :s
Wow ... interesting it seems like they were looking for 'something' I think you should divide how you store your PM's, this way if they find 1 stack they won't find all of it: maybe 1/3 buried out back, 1/3 hidden in home, and maybe 1/3 in a private vault not in your home.