Find out what types of tests you need to BE SURE that your Crohn's will not exacerbate or become real active again if you are reconnected, especially if you are doing OK with the ileostomy. The more surgery we have the more apt we are to form adhesions that may (or may not) cause issues. I speak from experience as mine caused severe small bowel obstruction issues. I did not have Crohn's mine was a whole 'nother story. But by personal experience I can say get fully tested prior to having a take down. Do research of your own, check with Mayo, then check with some other hospital web sites, or even get a few other opinions. You want this to work and work well if it is done.
Good luck, Rosemary