Hi... Welcome to HEALTHCARE MAGIC... I have gone through your query and can understand your concerns.. As per your complain you daughter seems to be suffering from Viral Infection causing the above described symptoms and the condition is known as HERPATIC GINGIVOSTOMATITIS in which there can be symptoms of cold and blisters in mouth and gums with swollen gums and there can also be fever. You should consult a physician and get him evaluated.. In case if the Viral Infection is diagnosed you should give him Tylenol or Motrin for pain relief.. Do cool compresses over gums for relief from Inflammation and reduction in swelling.. In case of pain in the sores on tongue a numbing gel like Oragel can be applied.. In severe cases antiviral Oral and topical Medication like Acyclovir therapy is given to the patient to reduce the duration of illness... Give him cool and bland diet.. Give him sufficient rest.. Maintain a good Oral hygiene and brush his teeth twice a day using an ultra soft toothbrush.. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora..