How wonderful that she is progressing so well. I hope everything goes textbook perfect for her and she is up and about in no time. Sounds like initially there may be some time to get everything going the way it should and tell her to be patient I suppose. When you're that young you just want to go go go...lol...in a totally different sense. I'm sure you'll get some great advice from others who can relate to this process.
I guess the real important thing is always applying a barrier cream of some kind after movements to keep the butt area from getting super irritated. Initially that will be very often until things settle down but I am sure you know all that already.
I researched before hubby's surgery (assuming and hoping he would ultimately get the j-pouch performed successfully) on trying to locate small travel type tubes of desitin for him to have in his pocket when not home. I never did find anything and tried making a one ounce travel container for him that I had home that was very pliable.....VERY difficult to try to get desitin into one of those!