My son has swollen cervical lymph nodes, he has them from birth. Dr. Say he's ok. The last 3ys he has them on his chest. Is the still from him growin?

Define swollen. Nodes in the head and neck are often more obvious because they are on top of muscles and not buried in the fat or tissue. They are usually pea sized at rest and swell to 1-2 cm or more when active/working. They often enlarge and shrink over a 3-4 week cycle. I rarely if ever find them on the chest, that would bother me.
Hmmm. Swollen cervical nodes are certainly common in children. I think that lymph nodes on the chest are not common. I would probably ask your doctor for a referral to a specialist such as infectious disease.