I feel for your friend! I don't think I had a kidney stone (the dr. could never say for sure if I did or didn't) but I did have a kidney infection which was plenty bad enough. Mine wasn't early in my pregnancy though, in fact I was hospitalized a week before my due date. What they did for me was give me 2 rounds of antibiotics through an IV over the course of 24 hours. The nurse said they couldn't really do what they normally do for kidney infections due to the pregnancy but the medicine was enough to clear it up. Hopefully that will work for your friend too.