Is yellow a roo or hen?

[PJinx]

Hello, everybody.I'm making a post again because I have six chickens and they're all fifteen weeks about. I have one which I am aware of that is a rooster.And they are blue, photo is attached so that you can see my rooster.And the rest of them, I was pretty sure are all hens, But now i'm starting to think that yellow might be a rooster as well. Yellow has not started to crow or anything of the such, but I've noticed that in the past week or so, yellow's comb and waddles have started to get bigger than all the other ones that I think are hens. Below I have attached photos for reference to see what you think. The photos are of- blue my rooster, yellow my potential rooster,and orange which i'm pretty sure is a hen.

 

[FamilyOfSeven]

I believe that yellow and orange are pullets.

 

[ShrekDawg]

I think she’s just a POL pullet

 

[Madhouse Pullet]

It looks like 2 pullets

 

[DemeterAD9]

Combs and waddles will get red and grow some on young hens who are close to sexual maturity (near laying age) so maybe that's why there's a change?

I have some 9 week olds and the 5 roosters have had combs like the one is question since week 7, though they are getting a bit bigger and darker in color now. Still no crows but I'm sure who is what.