Is it common for some birds to develop more quickly than others of the same breed and age? I have 3 BR about 22 weeks old. In the past 2 weeks the combs and waddles on two of them developed rather quickly and are now much bigger and red. The 3rd one still has a small and pale waddle and comb. She has now become the runt of the flock(I also have 3 RIR who are very developed)... Is this somewhat common? For a bird to develop at a slower rate like this? She is now smaller as well. She was just like the other 2 BR until they all of a sudden grew/matured, and she has not... yet. I hop she does soon because she does not seem happy as the immature runt.