<s>[INST] my 6 year old daughter almost 7 has had a knot under her jawline for over a year now, and her pediatrician would say it s her lymph nodes that are sweeling up due to mono, so they do tests and she shows up postive for mono, but wants you have mono you will always be postive for that. Anyways, dr said lymph nodes should go away, well they haven t. Could this be a cyst or something else? [/INST] Hello, Small lymph node ( less than 1cm) will persist but does not indicates any significant disease conditions. You can go for an ultrasound to confirm the diagnosis. If there is diagnostic confusion a fine needle biopsy may be needed. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Shinas Hussain, General & Family Physician </s>