Dark Ear Area?

[enggass]

I have 3 RIR Chicks about 2-1/2 weeks old. On the area behind the eyes - small circle, which I assume are ears? it is 'much' darker and obvious on one than the other 2 - less fur/feathers around the area as well. She seems fine otherwise. Have others noticed this and should I be concerned?
Thanks...
S

 

[redhen]

I think it will be okay..
Just keep an eye on it to be sure...

 

[enggass]

What would it be?

 

[enggass]

BUMP: Has no one else experienced this? Concerned...

 

[wildorchid053]

is one male and other 2 female?

 

[enggass]

Don't know yet... too young.