I have 3 white leghorns that i hatched with my kindergarten class. They will be 17 weeks old tomorrow. Their combs are large and bright red but no squatting yet. Considering that it is the middle of summer, i am expecting eggs any day. My other chickens (easter egger, black australorp, and lavender orpington) came into maturity in the middle of winter and waited until about 25 weeks to start laying. I am really hoping it is sooner rather than later.