I tried hatching my own eggs for the first time within the past month. I started out using my broody hen, but pulled the eggs at day 18-21 (they were set on different days...didn't know you should set on the same date) and put them in a new incubator after mama hen ate a hatching and pipped egg. The first hatch was still attached via the cord. It looked weak from the get-go. It never walked well, was completely lethargic, and frankly I expected it would die. It kept laying down, and rolling on its back. Its head was tilted to the side, and frankly it just didn't appear to have any sort of ability to hold its back up. It finally did die on its 3rd day of life. That same day, another was born. It appeared healthy. It was moving for the first 24 hours, seemed good. Then it too became lethargic. It was tired all the time, and same symptoms as the first. It died last night. Two days ago, the final chick in the bunch was born. Just as the first, it had the lethargy and all the other symptoms. I expect it will die while I'm at work today. What did I do wrong??? I got a syringe and fed the first in case it was dehydrated. I showed the chicks where food and water were, and they were always available. I splinted the feet in case they were spraddled, and put in a coffee cup with paper towels in case the legs just weren't strong enough.There is a chance the brooder lamp wasn't as warm as it should have been because I didn't have it lowered enough (again, didn't know). Pine chips and non-slip flooring mat in the brooder tub. But would that have caused these symptoms? I've read a bit about Marek's. Is that it??? Noteworthy: The chicks all hatched between days 24 and 26 of incubation. I expect that was potentially due to the extremely cold weather outside that we had in late January. There is also a chance that the broody left the eggs for more than a few minutes. I know one time she kicked one of the eggs out of the nest. Please help. I'm not trying to be a pain with posts. I am trying to learn from my mistakes. I have been told by my family that I am chicken obsessed because I have done so much research this week. It's all I talk about. I feel like it's my fault and I don't want to bring any more chickens into this world until I know what happened and if it's something I can change. Heartbroken. I'm not sure my four year old can handle more chicken deaths at this point.