Hi, The rash you described sounds like what happens with me. I have SLE and all the worrisome symptoms that come along with it, for example the Malar or Butterfly rash. I will wake up and my face will be fine and then a couple of hours later, I notice that the rash has appeared. Mine is sometimes red and other times white, itchy and raised. The sun and a flare-up of SLE are what most times I have noticed, when the rash appears but heat/cold and or UV lights will also contribute to it. The amount of time it lasts, is alwayz different (from a few minutes to weeks). It can be any of these things or absolutely nothing at all that causes the rash.
I have a low grade fever almost all the time and CKD (chronic kidney disease). I can deal with LGF except when I have to change my sheets in the middle of the night because of night sweats. I had a rash on one of my shoulders but that one felt like rubbing a piece of sandpaper and it became hairy and after a couple of months, it just went away by itself. Raynaud's and APS come along with my having Lupus also.
I hope I was able to help you and that you find out what is causing your daughters rash.