Our boy, Joey, got loose stools his first year and after lots of testing to rule out other things, we discovered he got it any time he ate chicken. We switched him to a new protein with no grains food and it worked well for him. But the symptoms would come back whenever he accidentally got chicken off and on throughout his life, so he never outgrew it and we treated it as an allergy. I hope you get to the bottom of her issues and she has normal stools and feels better very soon. Good luck!
Dillon has similar problems with chicken; whilst he loves eating it, it does not suit him at all, and worse still, it took us a long time to find out what it was, having initially blamed rice and grains on the problem. So he does not now have chicken - he is fine with most other meats, just not the chicken 8) hope that you get to sort the problem soon...