I have a 16 week old slw & blrw. This is my first experience with anything other than a single comb & I can't tell the boys from the girls!! I've seen a couple of the puffing their necks out at each other, which I'm assuming means they are little roo's, but then when I try to look at them I can't see a major difference. I do have a couple that are way smaller than the others, does that mean they are female? Any visual aids would be greatly appreciated! Thanks!