Child Having Pea Sized Movable Bump Under Jaw. What Could It Be?
It is possible that is a a lymph node, the lymph node under the jaw are the submandibular and submental lymph nodes. The cervical ones are further to the side, along the neck.
Submandibular lymph node respond to problems or infections in various areas including the sinuses,ears and phaynx (throat).
The submental drain the floor of the mouth and drain towards the submandibular nodes.
Even his cold was a few weeks ago, it commonly takes a while for the nodes to return to their normal size, especially because young children are repeatedly sick since their immune system is now developing.
Normally their size is noted and rechecked after a few weeks provided there are no infections in that time period.Usually the size decreases, if it increases and there are other nodes present then the doctor may consider doing a blood test- full blood count
You can consider taking him to his doctor to determine whether it is a lymph node.
I hope this helps, feel free to ask any other questions