Comb type

[Wallas]

I would not expect a big difference in the rate of comb development, unless one is male and the other is female.

Do you know what sex they are?

I'm fairly sure she is a female. This is the other that hatched from the same parents, I believe it's male.

 

[Wallas]

My females' combs never got big, they were all very small. Even the male's had smaller combs than most

Perhaps that means this chick is in fact a female as I suspected. The comb is basically nonexistent. It's smaller than the pea comb my ameraucana's had.

 

[NatJ]

I'm fairly sure she is a female. This is the other that hatched from the same parents, I believe it's male. View attachment 4211920

In that case, I think at least part of the difference in comb size is caused by what sex each one is.

If you've got a sex difference and a comb-type difference, you can get some really extreme differences (like in this case) or you can get confusing situations (a male with a small comb type and a female with a large comb type can make sexing much harder.)

And I agree with your thinking that the one is female and the other is male.