Differences in week old Plymouth Rock chicks

[rmansker]

I have 2 one week old Plymouth Rocks and one of them seems to be growing much faster than the other- is this normal? The smaller one you can barely see the wing feathers where the older looking one has much longer wing feathers. Also the bigger one has a larger patch of white on it's head. Could one have actually hatched a few days earlier and it's just an age difference or is one possibly a roo?

The smaller one seems to be perfectly healthy, although I was worried about her the first day and night as she seemed very lethargic and unsteady on her feet. Now she's actually the most lively one of the four I have ( I also have two RIR). Any guesses what's going on?

 

[rooster-red]

Sounds from your description like the chick with the larger head spot is a roo.

 

[rmansker]

I really wonder if I got a few older chicks and this one chick was the only one that was actually shipped right after it hatched. The 2 RIR I have look exactly the same as the more developed Plymouth Rock as far as their feather development. The primaries are about an inch long compared to the smaller PR whose primaries are just now starting to show.