Oh man! All the best, i hope she has no more pain and gets through this fast. I take it they have already broke those stones into little pieces, but even then this is always an ordeal with complications.
I heard (though i'm not a doctor or specialist) that drinking "hard" water leads to the build up of those stones, so if you or she is living in a region where the water comes from a carbonate-rich source, it might be a good idea to not use that in the future, but instead buy and use softer water.
Whatever, i hope she recovers, and fast.