Cats are coughing uncontrollably
My two cats have been having uncontrollable coughing fits lately--the younger, smaller one coughs very rapidly for approx 5 seconds, and the older larger one has these deep, longer coughing fits. Almost like wheezing. What could be the cause of this? They aren't feverish, they eat well, they do not vomit, they don't spit up hairballs, and they're both very energetic and playful. I'm afraid they might have torn some strings out of the couch, but I can't be sure. What should I be looking for? Thanks!