Okay so I got home today and went right outside to check on the babies who are in a brooder in their coop. I was sitting with them and they were all swarming around me and that's when I noticed that a few of them were stretching their necks and opening their beak like they were yawning. They didn't seem sick at all. In fact they were all over me to itch their little chests because they are losing the last of their fuzz and getting really itchy because of it. Should I be worried or is this a totally normal behavior? They are almost three weeks old (on Tuesday) and are eating Purina start and grow medicated crumbles have access to that and water 24/7 and are given treats of hard boiled eggs and occasionally other things such as oats, bananas or grass. We haven't gone much further into treats than that. They do have sand for grit and sand baths in their little area. The temp under their lights is running right between 90 and 80 and they have tons of room to get out of the light if they get hot so I don't think it's panting. Has anyone every had chicks do this or should I be concerned that they might be getting sick?