I have a chick that hatched out on February 12 and 1.5 weeks ago it got sick so I used corrid and it had started to feel better. Now today it’s laying down puffy again and its little tail is tucked. It’s the dark brown one. I don’t know what to do. I separated her from the rest of the flock I have there 7 in total I kept these 2 together cause they are both about the same size. These 2 are the smallest of the bunch. The others are a little bigger but they are obviously not all the same breed either. I do feed them a medicated chick mesh.