Well 'she' cock a doo's in the morning, but when I got her I was told she was a hen. The two other femals have combs too but don't make any noise. She is about a month older than the others so I had the thought she just might be a momma bird to the others?
That is very cute Its still hard to tell from the pictures. Do any of her feathers look different than your hens? Roosters have pointy feathers right before their tail that hang downward (saddle feathers) and on their neck (hackle feathers). They also have significantly larger combs and wattles. If she looks exactly like your others, she probably is a hen. Some hens have been known to crow, though I haven't seen it personally