I don't have Crohn's, but I do (more like did) have IBS. I saw a naturapathic doctor and it is gone now in part from removal of all dairy, gluten, sugar, corn, soy and much more so I know how hard it can be at times. Just about everything that isn't chicken, fish, turkey, or a vegetable or berry. Careful with starchy veggies though. Potatoes and carrots fit into this catagory. Potatoes should never be eaten because they raise blood sugar levels very high very fast. Carrots should be used only sparingly. Breads raise blood sugar levels very fast too. The only kinds of grains I ever have now are brown rice and quinoa.
Basically out of necessity now I make all of my food myself. That way I know exactly what goes into them. Lots of restaurants use the wrong kinds of oils like corn oil. The only two I ever use now are olive oil and coconut oil. Coconut oil is best to cook with because no trans fat can be made from heating it. Make sure she gets as much organic food as possible! That is very important. Probiotics should be helpful too and I am glad she is going on them. I use them everyday. Also helpful are plant-based enzymes because they make digestion much easier.
I really recommend that you read "Patient, Heal Thyself" by Jordan Rubin. The diet I follow is extremely similiar to the one listed in that book. The author himself was dying of terminal Crohn's disease and now is cured by following this diet. Another great book is "Dr. Mercola's Total Health Program".
Seeing a good naturapathic doctor couldn't hurt either. They may have really good ideas for what else can help. The one I see does saliva testing for hormonal imbalances and sure enough with the stress and anxiety I had, I definately needed supplements. I cannot tell you how much better it has made me feel! I take supplements for my thyroid and adrenals and use a progesterone cream. Very amazing stuff and I no longer have anxiety. Hormones are really important for overall health! Anyways, if you have any other questions, I'd be happy to answer! Good luck to the both of you and I hope she gets over this terrible disease!