My guess is the top one is a pullet and the other 2 are cockerels. I'm not 100% sure on that. I've had girls that squared off so thats not a for sure sign either. How I guess at this age is the roundness of the crest. The 2 on the bottom have the "swayback" look which I've found to be boys. the top one looks like it's crest is going straight up although I can't see the back of it. It looks like a girl to me. Don't count on me being right because I could be wrong. I recently had a frizzled silkie cockerel that I thought was a girl till it crowed. But then the frizzled ones are harder to tell most of the time. For me anyway and I raise alot of frizzled silkies.