Sorry to hear about your kids :-(. I follow a special diet, the Specific Carbohydrate Diet (SCD). Is that what your chiropractor is recommending? It healed my fistulas in 4 months, but I've seen some people say it could take as long as a year. It also reduces inflammation. It's certainly something worth considering for your kids. At first glance, it looks quite daunting, but once you get into a groove, it's easy to follow. Here are a few links, but I can give you much more if you need it:
http://www.pecanbread.com/ - focused on kids with autism, but there are several parents of kids with crohn's that frequent their yahoo group. You can go to http://health.groups.yahoo.com/group/pecanbread/ to ask questions about whether you think your kids would benefit. There's a lady named Diane whose daughter has been on the diet for 2 years, and would tell you their experience.
http://www.scribd.com/doc/11844050/Breaking-the-Vicious-Cycle-by-the-late-Elaine-Gottschall# - you can read (or download) Breaking the Vicious Cycle here. This will tell you the science behind the diet, outlines how you should follow it, and also has a ton of recipes.
http://www.breakingtheviciouscycle.info/ - the main website for BTVC and following SCD
http://health.groups.yahoo.com/group/BTVC-SCD/ - another yahoo group, this one centered around gut issues, that you can ask questions at
There are a slew of recipe sites too, which show how yummy the foods on the diet really are.
Good luck! I hope you find something to help your kids!
34 years old, Crohn's disease for 15 of them
Resection of ileocecal valve on 09/22/09
Current Meds: Pentasa, Effexor XR, Zyrtec
Supplements: 3 kinds of Fish Oil, Multi-Vitamin, B-Complex, Vitamins D, E, & K, Calcium, Magnesium, Enzymes
SCD since 12/01/08 - eating Stage 3 foods