We're very new to our chicken flock, our hens are just about 6 months old, recently started laying. Our Buff Orpington was breathing through her mouth more than the others recently, but it's been hot so we didn't worry. Yesterday and today, she's been doing it a lot more, breathing sounds stressed, she makes sneezing noises more frequently and just started making a loud noise every so often. Saw some milky white liquid pop out of her beak earlier today. She seems to be eating and drinking like normal, but I want to see what I should be doing? I've been doing some research but it seems like it could be SO many things. The other two hens are acting normal, just impacting the one bird. Thoughts?