Hi!! I have 3 chickens: a Barred Rock, a Buff Orpington, and an Easter Egger. My Barred Rock started laying about two weeks ago. But my other two have not even stated to do an egg squat. They're almost 28 weeks old now and I am a little surprised they're not laying yet. Does it have to do something with it being winter? Or is this normal for their breeds? Thanks soo much!!