But of course that one was a girl. Never had any doubt.
Really, a boy at this age will already have lots of pointy and super-shiny feathers all over neck, back, saddle(by the tail) and also on the wing bow. It's twice the shininess of the shine on some girls.
Some boys will involuntarily do the squat if touched/grabbed. Just look at feathers on neck and back.. if they're "soft" and round tipped exactly like your other BO, it's a girl.