Swelling In Neck, Ear Pain, Allergic To Smoke, Sour Candy Helps Salivary Glands. Is It Related To Lymph Nodes?

Hi, my friends daughter has been having sudden swelling in her neck below the ear followed with severe ear pain. this can last from 30 min to hours. If the child is given a sour candy and the saliva glands kick in salivating this seems for some reason to ease the pain in the ear and the swelling seems to decrease. The doctors can not seem to give her any answers. I was thinking it may have something to do with the glands, lymph nods, saliva glands, and or immune system responding to something. The child is allergic to smoke and in the pass this was a response her body would take in response to the smoke. Currently she has not been exposed to any kind of smoke. Her last reaction was while sitting in church singing and had been in the church approximately 30 min. prior to symptoms occurring. Would you happen to have any suggestions on what could possibly be taking place???