I have 5 hens that are 15 months old. All 5 were hatched together, but not all the same breed. One of them (a Light Brahma) began moulting almost 2 weeks ago but none of the others are showing any signs of losing any feathers at all. Wouldn't they moult at about the same time or am I just being a worry wart? She has a sister and there are 2 Australorps and a bantam EE. Just wondering if this is normal or could there be something wrong with Dolly - she looks so pitiful and has become more aggressive with the younger girls.