First, I'm sorry for what you and your daughter are going through. I have chronic pelvic pain, due to Interstitial Cystitis, Uterine Fibroids, and Endometriosis. I am inclined to believe that your daughter's pain is likely a result of Endometriosis. Does she have painful periods?
Unfortunately, this illness is under-diagnosed and undertreated. It took me 15yrs to get a diagnosis. Endometriosis can only be seen through laparoscopic surgery. If they find it while they're looking, they can remove the endometrial tissue, which can elevate the pain, at least temporarily. I advise you to go to a pelvic pain specialist. Ask about Endometriosis.
For me, three ablasion surgeries did not eliminate the pain. I went through a series of different suggested treatments, including Mirena IUD. For some, this works. For me, I bled HEAVILY for 9mos straight, and had horrible pain. Finally, I asked the doctor to remove it. He wanted me to try Lupton, as well, but after much research, I was very opposed to it. Also, they suggested a hysterectomy. Endometriosis can continue to grow and cause pain, even with hysterectomy.
Finally, at my request, he gave me a Depo shot. My periods stopped, and my pelvic pain is nearly nonexistent. Please get her checked for Endometriosis. Don't be to quick to get the Lupton shot; it will throw her into immediate early menopause. Also, it's very expensive, and only lasts a few months. Also, do not allow them to do a hysterectomy on her!
Feel free to ask me any questions, as I am a pain advocate, and have years of personal experience with pelvic pain. Good luck!