I have been caring for some Banty chicks, that my boyfriend ordered, while he is working out of town. They came in a week ago Thursday. He has a brooder box outside & I got it set up with a heat lamp, wood chips, & covered the hole. They were fine til the 2nd night the temperature dropped below freezing & we lost 3 of them. I moved them inside & noticed that 1 of the chicks was walking around but he seemed off balance & would fall over. By the end of the day he couldn't stand, kept his eyes closed, & was breathing heavily. He died the next morning & another chick was showing the same symptoms & died a couple hours after that. The rest of them seemed fine til 2 days later another chick started acting the same way & was dead when I got home from work. It has been 3 days now & I noticed another 1 was having difficulties standing last night. I found him laying on his back & when I picked him up he just fell to the side & curled his foot under him. He will still eat, drink, & isn't having any problems with his eyes but is breathing heavy & his legs don't seem to be working. This is the 4th chick that is showing signs of illness & will be the 7th one to die if he doesn't make it, all in less than 2 weeks. I am not very familiar with chickens & don't know much about them so I am learning as I go. My boyfriend knows more than me but is in another state right now. He is guessing that it might be mareks but isn't sure. Any input would be extremely helpful. Here is a picture of the chick that started showing signs of sickness last night.