Hello! I was wondering if anyone could help me determine the sex of these chicks? I ordered a box of pullets and got 8 warming chicks (SLW) in addition. Really hoping some of them are pullets as well. Some (6) have very flat spots where the others (2) have small combs. They are 3 weeks 2 days. Do you think there is a difference in sex or just speed of development? Thanks for any help!