In October we lost our 2 favorite chickens to a raccoon, a booted bantam rooster & calico Cochin hen. We had 6 eggs from her the week they died so we decided to incubate them. 4 eggs hatched and all seemed well with the chicks. At a month old, two of the chicks suddenly developed a limp, we isolated both, gave them vitamins & probiotics, but over the course of a month they both became almost completely paralyzed and could only flop around. They seemed to be suffering so we culled them. Fast forward to January the 2 remaining chicks are 3 months old, suddenly one starts limping and the other follows suit a few days later. Repeat isolation process again. Both chickens start to decline quickly, losing the ability to walk. Chicken #1 suddenly starts walking again after a month, she limps and needs to sit down to rest but is it not suffering. Chicken #2 is getting worse, now can no longer walk or even scoot around, he ends up helpless on his back if he tries to move, one wing is stuck sticking out at all times and he can’t lift his head up anymore. He was culled today. Could this be mareks? These chickens were raised in a brooder with other chickens from hatching eggs bought on EBay, it’s strange to me that this happened only to the chicks that hatched from my 2 chickens, any input welcome! Picture of rooster that was culled today is in post. 

Mareks?