At what age will female bantams get a Comb start showing?

[allmychickens]

cant tell, i would go cockeral because of wattle development, but pullet for comb, but then cockeral again for short beak...(I have noticed cocks have shorter beaks in silkies, in my experience)

 

[appps]

UPDATE
Just thought it might be interesting for others trying to sex their chicks but at 5 months it turned out to be the little black one was a rooster and the one with the rose comb everyone thought was a boy is a hen as is the other one and the silkie.

Guess it just goes to show they are tricky little beggars to sex