My pups are just over 4 weeks old, one of them keeps coughing occasionally. I first noticed it about a week ago, he coughed once and then I didnt hear it again until 2 days later when he coughed again. This morning he has coughed twice. Its almost like a hairball type cough if that makes sense?
He is perfectly well in himself, eating fine, no runny eyes/nose etc.

Its always just the one pup that does it, would you say a vet visit is necessary?

Coughing (if not Kennel cough) can be a sign of heart issues, fluid in lungs, so I would want teh vet to have a listen to heart and lungs.

Thanks, I shall nip him to the vets when I take my other dog in tomorrow.

Could be a 'wormy' cough.  How many times have they been wormed? 

Twice now, they just had their second lot on sunday.