About 3 weeks ago I bought chicks at tractor supply. 4 were out of the pullet leghorn bin, 2 from the California pullet bin, a variety of random pullets, and 1 from the rir straight run bin. So, they all started at the same sweet size. Now, I have a monster sized leghorn! After a week, I just thought maybe she was a rooster mixed in with the pullets, she and the single rir were about the same size. I’m thinking I ended up with 2 roosters, no biggie. Then she doubled everyone’s size, so I started thinking maybe she was older and got mixed in with the younger ones..... now, she’s even further ahead... 3 times her own breed, the California’s and 4 or more times bigger than the smaller breeds. She seems like she is tired, or she is breathing like she is turning into the hulk sometimes. I’ve looked her over, she looks rough from her big girl feathers growing, but I don’t see any abnormalities. Are they like people and some are just bigger? Could something be wrong? Any experience or ideas? Thanks