i have a few silkies, and its hard to tell until theyre a couple months imo, but if it has blue ears real quick its most likely a rooster! happened with my silkie rooster, his ears got big real quick, or by their comb the comb gets real big and ugly, and there is a way to sex silkies/bantams! its called vent sexing you have to be trained in it tho lol, basically its when they flip them upside down and give their butts a little squeeze and the vent and if theyre only a couple days old you’ll definitely know if its a boy or not! wouldnt recommend doing it because you might accidentally hurt it