I have taken Entocort, which is a steriod but is not absorbed much by the body. I have also used enteral nutrition, which involves going on a strict liquid diet using something like Ensure. I also take probiotics and a few other supplements.
Aside from steriods and Pentasa there are also immunosuppressants like 6-MP, Imuran, and methotrexate, and the biologics--Remicade, Humira, Cimzia, Tysabri. Many people take supplements and dietary changes might help.
What are your daughter's symptoms? I have not heard of polyps or lymphoid hyperplasia as part of Crohn's, but I'm not an expert, certainly not on pediatric disease. You say it is only "possible" Crohn's, then I would not think it wise to move on to stronger drugs till you are 100% sure. Maybe you could see another doctor for a second opinion if you have not already.
I would recommend that you check out the DragonPack IBD forum, which is dedicated to providing support and info for parents of kids with IBD.
July 2007 Drug-Induced Liver Injury
January 2008 Crohn's Ileitis
Currently trying... Enteral Nutrition, Flax Oil, VSL#3, Folic Acid, Vitamin E