My husband had surgery for bowel cancer in August 2013, and had a stoma bag afterwards. 13 months later, after tests, he was told that he was fit for a stoma reversal op, which took place in January of this year. All went well with the reversal, but unfortunately he contracted pneumonia, and was in ICU for 8 weeks, so it took a while for things to start working as they should down there, but all OK now. I remember the farting when he was on ICU, and us jokingly telling him that he was a pig, and the nurse said "no, no, farting is good!"
So pleased, Falconbird, that your son is doing so well.