I am relatively new to chickens. I have four hatchery silkies. Two appear to be cockerels, two appear to be pullets based on comb and behavior. However, my fifth chicken is a sizzle. I cannot figure out what it is. It looks like it may have a single comb, but I can't really tell (again, not a lot of experience with chickens). I do know that the comb has not grown or changed; whereas the roos have clearly developed combs. They're around 10-11 weeks ago. Any ideas? It's my favorite. Super sweet. Not dominant and doesn't chest bump with the cockerels.