MaryS, like your daughter, my daughter had constipation issues since she was little, but unlike your daughter, she didn't develop the LRQ pain until she was 16. And then came that loud stomach rumbling sound, which we now realize was due to the stricture she had developed. I dragged her from one doc to another, who were all clueless.
We finally managed to get a referral to a specialist who ending up misdiagnosing her, when she was aged 17. Ironic, because he was a pediatric gastroenterologist specializing in Crohn's, who had even written a book on the subject!! He suggested she de-stress and eat more fiber, saying, "I see a healthy kid!" (Just thinking about it makes me want to smack him.) A year after seeing him, she landed in the hospital and was finally correctly diagnosed.
So Claudine, we're all on your side.
"I actually asked them if the pain could be inflammation in her illeum and they looked at me like I was mad!" Who knows? Maybe they were just surprised you actually knew the term "ileum"