My 8 month has a pea sized bump it feels like a bone almost in the middle of his chest but more towards the left its on his breastbone.

Xray: Most bony lumps discovered in young children are related to congenital variations in rib cage. Most common variation is a duplicated anterior rib articulating with sternum.. Sometimes osteochondroma benign growth can be felt chest radiograph or x-ray most often clarifies cause of bony lumps.

Bump: It may be a piece of cartilage or something in the skin, however, without seeing it and possibly doing xray or another type of imaging, it's impossible to correctly diagnose the condition.