Sexing Blue Laced Red Wyandotte Bantam Chicks...help!

[purplesquirrel]

So I hatched 4 pure chicks and sold one (with another breed).

So I have 3 now. One is blue ish grey with faded chipmunk pattern and dark, - slow wing dev.
One is pretty much just gold, red and brown with strong chipmunk pattern - fast wing dev.
And the third is almost purple grey with faint light brown chipmunk pattern - slow wing dev.

Can I bet the fast wing development one is a girl and the other 2 are boys? Or is it just varied genes? Because they really are a lot more developed than the other two.
They're 8 days old now but I have some images of two of them on here I think...



If anyone can help me that would be great. I really can't have do anymore cockerels, they drive me nuts and I spend so long trying to sell them or give them away!
Many thanks.x

P.s can upload feather photos if that helps.

 

[Wyandottes7]

Males sometimes feather in slower. But, it is by no means 100% accurate. Different birds, even within a breed, feather in at different rates.

 

[BantamLover21]

Feather growth speed is not a reliable method of sexing (though cockerels do often feather slower), so I wouldn't assume any are cockerels/pullets yet.