From: Pittsburgh, PA
It's also possible that there are still problems with the new DNS server routing (the thingy that tells the internet who and where EBSQ is), although a) that's not terribly likely considering how long we've been back online and b) that's a huge problem if that IS what's going on!
Definitely have your sister run through mindful's suggestions. Also have her make sure she hasn't accidentally "blocked" our site. But if none of that helps, PLEASE let us know so we can continue to research the problem.
Also, who is your sister's ISP? And can she access the site from work, for example?
Get out of the vacuum and express yourself!