Petechiae

Hi my daughter keeps getting a petechiae type rash on the crease of her elbows. With treatment with emollient is slowly goes but then comes right back. I haven't thought anything of it but just recently she has had a few very minor nosebleeds, complains of headaches and tummy aches and mentioned twice that her hip hurts. She also has had a couple of bruises come up that she cant remember any reason for. In the process of googling how to treat her rash it has obviously mentioned leukaemia which is worrying but I don't want to be that anxious mum. I will be doing an e consult to try and speak to a gp but the sensible part of me is wondering if treating her rash and it going away temporarily means it's not a petechiae we are dealing with and rather a dermatitis? Anyone with experience of this type of rash?