Why were you looking in her home directory? :)

Totally tangential to the issue discussed, but years ago I was doing interviews of college kids for dev jobs in a unix env. The recent graduates had had some unix in school, but not much. When asked some questions about it, one candidate let slip that he wanted to see what other people were doing so he started looking in their home dirs.

We hired him. He was absolutely fantastic.

Well now I could just say I was running tar and saw "resume" fly across the screen.

Or maybe because she had a problem I was in her directory and saw a suspicious file.

More than likely I was doing recon - I'm curious, so anything is possible.

Was your sister working for you? If so, why? If not, how is this connected?

Also I'm not sure how the existence of a root user plays a part because on the vast majority of unix systems the default home directory permissions are permissive read (this was true in 1987 and is still true now) and if your sister didn't know about root users it seems fairly unlikely that she knew about chmod.