What food to eat after having Cecal Volvulus surgery?

My daughter had terrible stomach pains and went to the hospital turns out she had Cecal volvulus and got emergency surgery. She had no problems before this. Now it has been 7 weeks since the surgery . What are foods that you should eat and what foods should you not eat? Several foods she tries she gets diarrhea. No stomach pains or anything . Any advice would be appreciated. Thank you