One of my baby chicks (who is about a week old now) has always been almost double the size of the others since it was only 2 days old ! She is a buff orpington, but we have one other buff orpington chick and it is almost half the size as this one. We know for a fact that it is not older than the others, it is just large. Could this mean it is a rooster? The one I'm talking about is the larger yellow one on the far left. In this picture, the yellow ones (buff orpingtons) and the red ones (rhode island reds) are about 3 days old. The brown ones and black one are 7-9 old in this picture, so please don't compare it to the brown ones because they are about a week older than the yellow and red ones. Why is it so much larger? They're suppose to all be female, but since it is so large it makes me think its going to be a rooster. Are some chickens just born larger then others? Thanks !