I have a bird that seems to be breathing funny. It is a 4 week old black barred PR. She lives with 5 other chicks in a brood box lined with pine shavings. they eat medicated crumbles and they get grit. They also get outside time since the weather here is amazing right now. She seems to always breath heavy and even has a soft chirping sound when she exhales. She has always been like this since I got them at the farm store. she eats, drinks and poops normal and even displays normal chicken behavior. all the other chicks have no issues. I assume that if it was a disease of some sort, it would have spread to the others by now. They have all been living together since I got them 4 weeks ago. Any help or suggestions would be greatly appreciated.