Hi Everyone. I can't figure out what is wrong with one of my chicks. I hatched 7 eggs back in Nov and 6 are still alive. However, out of the 6 one of the chicks did not grow. It started out like the others but at around 3-4 weeks just stopped growing. The other chicks are about 3 times bigger now. It is also not as strong as the others and stays ruffled up like it's cold. I still have it under heat and take it out with the others when it's warm enough. It eats, drinks and poops normally. The only other odd thing is a small bump on the top of it's head that has stayed the same since birth. This chick is almost 10 weeks old. Any ideas?