There are certainly individual differences and sometimes one will fool us. I hope they're all girls. Look at this comparison of two RIRs I hatched at four weeks old-brother and sister-comb, wattle and leg differences, first the boy then the girl (rooster-red, this is Scarlett):
Here is one of my SLW girls at about three months old for you to see her comb:
Here is one of my SLW girls at about three months old for you to see her comb: