I got 3 ISA Brown day old chicks. They are now 4 weeks old. One (the chick on the left) was the darkest red, definitely indicating pullet. She didn’t get her tail feathers for a full week after all the other chicks, and was much slower to develop wing feathers. I had read males are slower to feather, but being a color sex chick I didn’t think much about it. Today, I noticed how much larger her comb is compared to the others. I did a little research, and found out only the 1st generation is color sexed. Could I possibly have a little cockerel?