Thanks everyone for the advice and information.
My son is getting the probe that goes through his nose and needs to be removed manually. Fortunately, he will be asleep for the endoscopy when they place the probe. I have done a little research since I last posted and I guess it shouldn't be too bad for him. I don't know if doc will be doing any biopsies yet, so maybe that will be the worse part - having a sore throat later that day. Just like all moms, I hate the idea of anything unpleasant happening to my child so I probably overworry about the effect of these tests. Also doctor mentioned surgery about five minutes after talking to me which kind of set my nerves on edge as well.
Also, for anyone who might run across this thread looking for info for their own child, I found a site that allows users to download a storybook for young kids that explains what happens to them when they have a ph probe and an endoscopy. My son really like reading it! (I hope this link is allowed) The link is http://www.prevakids.com/gerd-tools/ph-probe.aspx.
UC diagnosed 10/05, first symptoms 1983
asacol 12/daily and rowasa as needed
Trying out Digestive Fitness Probiotic
past rx: colozal, lialda, canasa