Is the child afebrile and does her normal activities? If so, fifth disease is a possibility with the accompanying cutaneous eruptions. Other viral exanthems (caused by Epstein Barr, rubeola, rubella, enterovirus, etc) may also be considered until a specific diagnosis is reached. Viral infections are usually self limiting, so that if the patient's immune system is supported enough to fight it, patient gets well with just bed rest and good nutrition. For now, keep an eye on her for spikes in temperature and make sure she doesn't start scratching to prevent secondary bacterial infections of the lesions.
I hope she gets well soon