Although it is not something to go off of completely cause some girls can color up real nice but the green on the head scream male. Usually you see pinks or nude type coloring on the face by that age. Blue or purple cheeks both male and female can have that.
There is something I look for on a female, and it's very unscientific, but has been reliable for me. I call it the "swoosh", and it's a pattern right by the shoulder. I'm not seeing that in any of them. Add that to tail base, I say 3 males