horsey little one is more prone to chest problems as so wee. They have yet to learn how to cough and sneeze (and pick nose). So long as he does not have a temp, his breathing seems ok, look at his chest - if his chest bone is going in dramatically then get it checked, is he a good colour, distressed at all, drowsy, off his food, vomiting etc. if at all worried get him looked at. With a baby under 1 any GP should be willing to see as an emergency that day. It is more likely to just be snuffles. DS has the snuffles, and has had them since he was about a week old as his sisters love sharing.