Help sexing silkies please

[Kelnobbs]

Hi I have 4 9 week old silkies, can anyone hazard a guess to their sex please?
Please excuse the dirty faces, they had some corn on the cob lol

 

[NatJ]

I'm guessing the first one might be a male, because the comb looks bigger than some of the others? But I really don't know silkies.

Maybe someone else will have an opinion, or you might be stuck waiting for them to crow or lay eggs (which feels like forever to wait!)