My Son Has Been Having A Swollen Jaw Line Like

My son has been having a swollen jaw line like mumps. Negative for mono and lymph node not swollen. No fever and no pain. The scheduled lymph node biopsy did not happen because the doctor said the lymph node is not swollen. He said he needs to be seen by ENT speCIALIST. WHAT DO YOU THINK IS HAPPENING. The swelling is worst first thing as soon as he wakes up and sometimes would go down as day progresses. I am worried.