I have just started my life as a chicken mama with 16 chicks! They are now 2 weeks old. One of the chicks seems to have trouble pooping. She strains, peeps loudly, and gets kind of puffed up when going. I can easily milk the vent and assist her. The poop doesn't seem to be hard or dry, there is no blockage or swelling. This has only been happening for the last 3 days. I did give the chicks a little yogurt and scrambled egg mixed in chick food just before this started. None of the other chicks are having trouble. Suggestions? I took the pine shavings out of the brooder in case she was eating them. She eats and drinks normally and is active. Thanks!