Even that tiny smidgeon of white?
I've seen pure ccl girls with a smidgeon of a dot. (At least if I recall correctly)
In pure cream legbars, the girls are barred also, that's why they may have a white spot. If you're mixed chicks are a Marans roo over CCL hens then any white spot on the head indicates male. If it was a CCL roo over marans hens then they would all be barred (I think that's right)