At 2 1/2 weeks old, my one rooster chick is half the size of the others - and he has no tail feathers yet. I've watched him eating and drinking and there doesn't seem to be any issue with him and all the ladies. Is it normal for him to be so much smaller? He is a RIR. The other 16 chicks are RIR, BA (which are huge compared to all the others), Speckled Sussex and Barred Rock.