J.C.
many great suggestions already. Also, is she is having a tummy bug, there is usu. elevated yeast in the bowel and it causes a bad rash. My daughter had this when she was 2 yrs old. Even w/ only using soft towels and water (no wipes). It only got worse. Went to the Dr. and she told me to go to the store and buy Lotrimin or Gynelotrimin and use it. It was all she needed. I believe I even used her extra heavy-duty rash cream on top of it so it wouldn't wipe away as easily. Ralph's has a great diaper rash cream w/ higher % of zinc oxide. (I believe that is the active ingredient). I think it is the Kroger brand. Aquaphor is great too.
Hope this helps!