As long as he's not in pain and is getting output, he should be fine. Just make sure he's drinking plenty of fluids to keep things flowing. Now, if he stops getting output, has abdominal pain, and starts to vomit, he could have a blockage and should go to the ER right away.
Dx'd Crohn's in '99 at age 28. Proctocolectomy and ileostomy in '06.
Disease-free and medicine-free since surgery and very thankful to be healthy again.